Automobile body-coating method

ABSTRACT

An automobile body-coating method which comprises optionally subjecting an aluminum material in the automobile body to a surface treatment, followed by subjecting to an oxidizing film treatment, essentially or optionally, respectively and successively forming a curable electrodeposition coating film, a water based chipping primer coating film, an intercoat coating film, and a curable topcoat coating film, or comprises applying a film racing material onto an aluminum material or coating film-coated aluminum material, and comprises forming respective multi-layer coating films onto the steel material in the automobile body respectively.

BACKGROUND ART

[0001] (1) Field of the Invention

[0002] The present invention relates to a coating method of anautomobile body partly or wholly consisting of an aluminum material oran oxidized aluminum material, which method is capable of forming acoating film showing good coating film finished appearance in definitionproperties, smoothness and the like, and good coating film performancesin corrosion resistance, fabrication properties and the like.

[0003] The present invention also relates to an automobile body-coatingmethod comprising applying a film facing material onto the surface of analuminum material or an aluminum-material-coated steel material in anouter plate area and/or an inner plate area-of an automobile bodycomprising an aluminum material, an aluminum material-coated steelmaterial or an aluminum material and steel material-combined metalmaterial, and capable of forming a coating film showing good coatingfilm finished appearance in definition properties, smoothness and thelike, and good coating film performances in corrosion resistance,fabrication properties and the like.

[0004] (2) Description of Background Art

[0005] An automobile body-coating method comprising subjecting anautomobile body consisting of a steel material to a chemical treatment,followed by a primer coating, and a topcoat coating, is well known inthe art.

[0006] Recently, in the field of the automobile, on one hand, anautomobile body weight is increased due to improvements in collisionsafety performances and increase in standard trims, and on the otherhand, remarkable improvements in fuel cost are demanded from thestandpoint of global environment problems. As an approach to satisfy theabove demand, an attempt to replace a part or all of the automobile bodycomprising a steel material with an aluminum material has been proposedso as to decrease a total weight of the automobile body. However,application of the conventional coating method to an automobile bodypart comprising the aluminum material makes it impossible to form acoating film showing good finished appearance and good coating filmperformances.

[0007] The present inventors made intensive studies to find out that acoating film formed by a coating method comprising specified steps cansolve the above problems, resulting in completing the present invention.

[0008] A use of an aluminum material in a part of the automobile body,for example, hood, roof, bonnet and the like, may produce such problemsthat vibration may produce noises while the automobile is running.

[0009] In the art, a crosslinkable resin coating composition such as amelamine-curing resin coating composition, isocyanate-curing resincoating composition, oxidation-curing resin coating composition and thelike is coated directly onto an interior part or exterior part of theautomobile. However, the direct coating onto the automobile bodyproduces such problems that a selection of an optimum coating method istroublesome, that a uniform coating film thickness is difficult toobtain, that coating drawbacks due to coating, for example, cissing,spitting, foreign particles and the like, may develop, that the coatingcomposition necessary for coating may be consumed in an excess amount,that safe performances of a working environment for coating and controlsof safety and health are difficult, that difficulties of recovering usedcoating films are undesirable from the standpoint of environmentalpollution, that use of the spray coating as usual is unable to provide awide application in appearance, that finishing is planar and short ofsteric feeling, and the like.

[0010] The present inventors made intensive studies to find out that amethod of applying a film onto the aluminum material can solve the aboveproblems, resulting in completing the present invention.

SUMMARY OF THE INVENTION

[0011] The present invention firstly provides an automobile body-coatingmethod which comprises optionally subjecting an outer plate area and/oran inner plate area of an automobile body comprising an aluminummaterial, an aluminum material-coated steel material or an aluminummaterial and steel material-combined metal material to a surfacetreatment, successively followed by coating a heat-curableelectrodeposition coating composition to form a curableelectrodeposition coating film, (1) coating a heat-curable water basedintercoat coating composition to form a water based intercoat coatingfilm or coating a heat-curable intercoat powder coating composition toform an intercoat powder coating film, (2) coating a water basedchipping primer to form a water based chipping primer coating filmfollowed by coating a heat-curable water based intercoat coatingcomposition to form a water based intercoat coating film or coating aheat-curable intercoat powder coating composition to form an intercoatpowder coating film, or (3) coating a water based chipping primer toforma water based chipping primer coating film, and coating a topcoatcoating composition to form a curable topcoat coating film, respectivecoating films being heat cured independently from each other to cure allof the respective coating films, or at least one multi-layer coatingfilm selected from the group consisting of successively formed at leasttwo-layer coating films being heat-cured simultaneously and at least oneremaining coating film being independently cured respectively(hereinafter referred to as a first invention).

[0012] The present invention secondly provides an automobilebody-coating method for coating an outer plate area and/or an innerplate area of an automobile body comprising an oxidized aluminummaterial or an oxidized aluminum material and steel material-combinedmetal material, which method comprises (1) electrodeposition coating aheat-curable electrodeposition coating composition onto the surface ofthe oxidized aluminum material in the outer plate area and/or the innerplate area of the automobile body to form an electrodeposition coatingfilm followed by heat curing, optionally the steel material beingsubjected to a surface treatment followed by being subjected to anelectrodeposition coating, or (2) coating a heat-curable water basedintercoat coating composition or a heat-curable intercoat powder coatingcomposition onto the outer plate area and/or the inner plate area of theautomobile body to form a water based intercoat coating film or anintercoat powder coating film respectively followed by creating acurable topcoat coating composition to form a curable topcoat coatingfilm, and heat curing both coating films independently from each otheror simultaneously, optionally the steel material being subjected to anelectrodeposition coating (hereinafter referred to as a secondinvention).

[0013] The present invention thirdly provides an automobile body-coatingmethod which comprises applying a film facing material onto the surfaceof an aluminum material or an aluminum material-coated steel material inan outer plate area and/or an inner plate area of the automobile bodycomprising an aluminum material, an aluminum-coated steel material or analuminum material and steel material-combined metal material, the filmfacing material being applied onto the surface of an aluminum materialwhich is optionally subjected to a surface treatment, followed by beingsubjected to an oxidizing treatment (hereinafter referred to as a thirdinvention).

DETAILED DESCRIPTION OF THE INVENTION

[0014] The first invention provides in a first embodiment respectively;

[0015] 1. an automobile body coating method which comprises optionallysubjecting an outer plate area and/or an inner plate area in anautomobile body comprising an aluminum material, an aluminummaterial-coated steel material or an aluminum material and steelmaterial-combined metal material to a surface treatment, successivelyfollowed by coating a heat-curable electrodeposition coating compositionand heat-curing, coating a heat-curable water based intercoat coatingcomposition or a heat-curable intercoat powder coating composition andheat-curing, and coating a curable topcoat coating composition andcuring;

[0016] 2. an automobile body-coating method which comprises optionallysubjecting an outer plate area and/or an inner plate area in anautomobile body comprising an aluminum material, an aluminum-coatedsteel material or an aluminum material and steel material-combined metalmaterial, successively followed by coating a heat-curableelectrodeposition coating composition and setting or predrying, coatinga heat-curable water based intercoat coating composition or aheat-curable intercoat powder coating composition and heating to cureboth an electrodeposition coating film and an intercoat coating filmsimultaneously, and coating a curable topcoat coating composition andcuring;

[0017] 3. an automobile body coating method which comprises optionallysubjecting an outer plate area and/or an inner plate area in anautomobile body comprising an aluminum material, an aluminummaterial-coated steel material or an aluminum material and steelmaterial-combined metal material to a surface treatment, successivelyfollowed by coating a heat-curable electrodeposition coating compositionand setting or predrying, coating a heat-curable water based intercoatcoating composition or a heat-curable intercoat powder coatingcomposition and setting or predrying, coating a heat-curable topcoatcoating composition, and heat-curing an electrodeposition coating film,an intercoat coating film and a topcoat coating film simultaneously; and

[0018] 4. an automobile body-coating method which comprises optionallysubjecting an outer plate area and/or an inner plate area in anautomobile body comprising an aluminum material, an aluminummaterial-coated steel material or an aluminum material and steelmaterial-combined metal material to a surface treatment, successivelyfollowed by coating a heat-curable electrodeposition coating compositionand heat-curing, coating a heat-curable water based intercoat coatingcomposition or a heat-curable intercoat powder coating composition andsetting or predrying, coating a heat-curable topcoat coatingcomposition, and heat-curing an intercoat coating film and a topcoatcoating film simultaneously.

[0019] The first invention provides in a second embodiment respectively;

[0020] 1. an automobile body-coating method which comprises optionallysubjecting an outer plate area and/or an inner plate area in anautomobile body comprising an aluminum material, an aluminummaterial-coated steel material or an aluminum material and steelmaterial-combined metal material to a surface treatment, followed bysuccessively forming a heat-curable electrodeposition coating film, awater based chipping primer coating film, a heat-curable water basedintercoat coating film or a heat-curable intercoat powder coating filmand a curable topcoat coating film (4C);

[0021] 2. an automobile body-coating method which comprises optionallysubjecting an outer plate area and/or an inner plate area of anautomobile body comprising an aluminum material, an aluminummaterial-coated steel material or an aluminum material and steelmaterial-combined metal material to a surface treatment, successivelyfollowed by coating a heat-curable electrodeposition coating compositionand heat-curing, coating a water based chipping primer coatingcomposition and heat-curing, coating a heat-curable water basedintercoat coating composition or a heat-curable intercoat powder coatingcomposition and heat-curing, and coating a curable topcoat coatingcomposition and curing;

[0022] 3. an automobile body-coating method which comprises optionallysubjecting an outer plate area and/or an inner plate area of anautomobile body comprising an aluminum material, an aluminummaterial-coated steel material or an aluminum material and steelmaterial-combined metal material to a surface treatment, successivelyfollowed by coating a heat-curable electrodeposition coating compositionand setting or predrying, coating a water based chipping primer coatingcomposition and heat-curing, coating a heat-curable water basedintercoat coating composition or a heat-curable intercoat powder coatingcomposition and heat-curing, and coating a curable topcoat coatingcomposition and curing;

[0023] 4. an automobile body-coating method which comprises optionallysubjecting an outer plate area and/or an inner plate area of anautomobile body comprising an aluminum material, an aluminummaterial-coated steel material or an aluminum material and steelmaterial-combined metal material to a surface treatment, successivelyfollowed by coating a heat-curable electrodeposition coating compositionand heat-curing, coating a water based chipping primer coatingcomposition and setting or predrying, coating a heat-curable water basedintercoat coating composition or a heat-curable intercoat powder coatingcomposition and heat-curing, and coating a curable topcoat coatingcomposition and curing;

[0024] 5. an automobile body-coating method which comprises optionallysubjecting an outer plate area and/or an inner plate area of anautomobile body comprising an aluminum material, an aluminummaterial-coated steel material or an aluminum material and steelmaterial-combined metal material to a surface treatment, successivelyfollowed by coating a heat-curable electrodeposition coating compositionand heat-curing, coating a water based chipping primer coatingcomposition and heat-curing, coating a heat-curable water basedintercoat coating composition or a heat-curable intercoat powder coatingcomposition and setting or predrying, and coating a curable topcoatcoating composition and curing;

[0025] 6. an automobile body-coating method which comprises optionallysubjecting an outer plate area and/or an inner plate area of anautomobile body comprising an aluminum material, an aluminummaterial-coated steel material or an aluminum material and steelmaterial-combined metal material to a surface treatment, successivelyfollowed by coating a heat-curable electrodeposition coating compositionand setting or predrying, coating a water based chipping primer coatingcomposition and setting or predrying, coating a heat-curable water basedintercoat coating composition or a heat-curable intercoat powder coatingcomposition and heat-curing, and coating a curable topcoat coatingcomposition and curing;

[0026] 7. an automobile body-coating method which comprises optionallysubjecting an outer plate area and/or an inner plate area of anautomobile body comprising an aluminum material, an aluminummaterial-coated steel material or an aluminum material and steelmaterial-combined metal material to a surface treatment, successivelyfollowed by coating a heat-curable electrodeposition coating compositionand setting or predrying, coating a water based chipping primer coatingcomposition and heat-curing, coating a heat-curable water basedintercoat coating composition or a heat-curable intercoat powder coatingcomposition and setting or predrying, and coating a curable topcoatcoating composition and curing;

[0027] 8. an automobile body-coating method which comprises optionallysubjecting an outer plate area and/or an inner plate area of anautomobile body comprising an aluminum material, an aluminummaterial-coated steel material or an aluminum material and steelmaterial-combined metal material to a surface treatment, successivelyfollowed by coating a heat-curable electrodeposition coating compositionand heat-curing, coating a water based chipping primer coatingcomposition and setting or predrying, coating a heat-curable water basedintercoat coating composition or a heat-curable intercoat powder coatingcomposition and setting or predrying, and coating a curable topcoatcoating composition and curing; and

[0028] 9. an automobile body-coating method which comprises optionallysubjecting an outer plate area and/or an inner plate area of anautomobile body comprising an aluminum material, an aluminummaterial-coated steel material or an aluminum material and steelmaterial-combined metal material to a surface treatment, successivelyfollowed by coating a heat-curable electrodeposition coating compositionand setting or predrying, coating a water based chipping primer coatingcomposition and setting or predrying, coating a heat-curable water basedintercoat coating composition or a heat-curable intercoat powder coatingcomposition and setting or predrying, and coating a curable topcoatcoating composition and curing.

[0029] The first invention provides in a third embodiment respectively:

[0030] 1. an automobile body-coating method which comprises optionallysubjecting an outer plate area and/or an inner plate area of anautomobile body comprising an aluminum material, an aluminummaterial-coated steel material or an aluminum material and steelmaterial-combined metal material to a surface treatment, successivelyfollowed by forming a heat-curable electrodeposition coating film, awater based chipping primer coating film, and a curable topcoat coatingfilm;

[0031] 2. an automobile body-coating method which comprises optionallysubjecting an outer plate area and/or an inner plate area of anautomobile body comprising an aluminum material, an aluminummaterial-coated steel material or an aluminum material and steelmaterial-combined metal material to a surface treatment, successivelyfollowed by coating a heat-curable electrodeposition coating compositionand heat-curing, coating a water based chipping primer coatingcomposition and heat-curing, and coating a curable topcoat coatingcomposition and curing;

[0032] 3. an automobile body-coating method which comprises optionallysubjecting an outer plate area and/or an inner plate area of anautomobile body comprising an aluminum material, an aluminummaterial-coated steel material or an aluminum material and steelmaterial-combined metal material to a surface treatment, successivelyfollowed by coating a heat-curable electrodeposition coating compositionand setting or predrying, coating a water based chipping primer coatingcomposition and heat-curing, and coating a curable topcoat coatingcomposition and curing;

[0033] 4. an automobile body-coating method which comprises optionallysubjecting an outer plate area and/or an inner plate area of anautomobile body comprising an aluminum material, an aluminummaterial-coated steel material or an aluminum material and steelmaterial-combined metal material to a surface treatment, successivelyfollowed by coating a heat-curable electrodeposition coating compositionand heat-curing, coating a water based chipping primer coatingcomposition and setting or predrying, and coating a curable topcoatcoating composition and curing; and

[0034] 5. an automobile body-coating method which comprises optionallysubjecting an outer plate area and/or an inner plate area of anautomobile body comprising an aluminum material, an aluminummaterial-coated steel material or an aluminum material and steelmaterial-combined metal material to a surface treatment, successivelyfollowed by coating a heat-curable electrodeposition coating compositionand setting or predrying, coating a water based chipping primer coatingcomposition and setting or predrying, and coating a curable topcoatcoating composition and curing.

[0035] The automobile body-coating method in the first embodiment of thefirst invention is characterized in that the coating method comprisesthe following steps, a step of coating a heat-curable electrodepositioncoating composition onto an automobile body partly or totally comprisingan aluminum material, a step of coating a water based or powderintercoat coating composition, and a step of coating a curable topcoatcoating composition, that respective coating films are cured byparticular curing methods, and that the aluminum material has a degreeof surface roughness of 0.2 μm or less in terms of Ra.

[0036] The coating method in the first embodiment of the firstinvention, in the case where a sole metal base material such as analuminum material, an aluminum material-coated steel material and thelike is used as a base material of the automobile body, may be carriedout by the following methods, for example,

[0037] (1) a method which comprises subjecting the metal base materialto a press molding into a predetermined part material such as an enginehood, fender panel and the like, followed by optionally subjecting to asurface treatment, assembling the surface-treated part material to theautomobile body, respectively subjecting to an electrodepositioncoating, an intercoat coating and a topcoat coating;

[0038] (2) a method which comprises subjecting the metal base materialto a press molding into a predetermined part material, followed byoptionally subjecting to a surface treatment, subjecting to anelectrodeposition coating, assembling the electrodeposition-coated partmaterial to the automobile body, respectively subjecting to an intercoatcoating and a topcoat coating;

[0039] (3) a method which comprises subjecting the metal base materialto a press molding into a predetermined part material, followed byoptionally subjecting to a surface treatment, respectively subjecting toan electrodeposition coating and an intercoat coating, assembling theintercoat-coated part material to the automobile body, and subjecting toa topcoat coating; and

[0040] (4) a method which comprises subjecting the metal base materialto a press molding into a predetermined part material, followed byoptionally subjecting to a surface treatment, respectively subjecting toan electrodeposition coating, an intercoat coating and a topcoatcoating, and assembling the topcoat-coated part material to theautomobile body.

[0041] The coating method in the first embodiment of the firstinvention, in the case where an aluminum material and a steelmaterial-combined metal material is used as a base material of theautomobile body, may be carried out by the following methods, forexample,

[0042] (1) a method which comprises assembling to the automobile body asurface-treated aluminum part material prepared by subjecting analuminum material to a press molding into a predetermined part materialsuch as an engine hood, fender panel and the like followed by optionallysubjecting to a surface treatment, and a surface-treated steel partmaterial prepared by subjecting a steel material to a press molding intoa predetermined part material such as an engine hood, fender panel andthe like, followed by subjecting to a surface treatment, followed byrespectively subjecting to an electrodeposition coating, an intercoatcoating and a topcoat coating;

[0043] (2) a method which comprises assembling to the automobile body anelectrodeposition-coated aluminum part material prepared by subjectingan aluminum material to a press molding into a predetermined partmaterial such as an engine hood, fender panel and the like, followed byoptionally subjecting to a surface treatment, and subjecting thesurface-treated aluminum part material to an electrodeposition coating,and an electrodeposition-coated steel part material prepared bysubjecting a steel material to a press molding into a predetermined partmaterial such as an engine hood, fender panel and the like, followed bysubjecting to a surface treatment, and subjecting to anelectrodeposition coating, followed by respectively subjecting to anintercoat coating and a topcoat coating;

[0044] (3) a method which comprises assembling to the automobile body anintercoat-coated aluminum part material prepared by subjecting analuminum material to a press molding into a predetermined part materialsuch as an engine hood, fender panel and the like, followed byoptionally subjecting to a surface treatment, respectively subjectingthe surface-treated aluminum part material to an electrodepositioncoating and an intercoat coating, and an intercoat-coated steel partmaterial prepared by subjecting a steel material to a press molding intoa predetermined part material such as an engine hood, fender panel andthe like, followed by subjecting to a surface treatment, andrespectively subjecting the surface-treated steel part material to anelectrodeposition coating and an intercoat coating, followed bysubjecting to a topcoat coating; and

[0045] (4) a method which comprises assembling a topcoat-coated aluminumpart material prepared by subjecting an aluminum material to a pressmolding into a predetermined part material such as an engine hood,fender panel and the like, followed by optionally subjecting to asurface treatment, and respectively subjecting the surface-treatedaluminum part material to an electrodeposition coating, an intercoatcoating and a topcoat coating, and a topcoat-coated steel part materialprepared by subjecting a steel material to a press molding into apredetermined part material such as an engine hood, fender panel and thelike, followed by subjecting to a surface treatment, and respectivelysubjecting the surface-treated steel part material to anelectrodeposition coating, an intercoat coating and a topcoat coating.

[0046] In addition to the above methods, for example, orders ofrespective coating steps of the aluminum material and the steel materialmay be varied. Specifically, a steel material may be subjected to apress molding into a predetermined part material such as an engine hood,fender panel and the like, followed by assembling the steel partmaterial to the automobile body, and respectively subjecting to asurface treatment and an electrodeposition coating to prepare anelectrodeposition-coated steel part material-assembled automobile body.

[0047] Separately, an aluminum material is subjected to a press moldinginto a predetermined part material such as an engine hood, fender paneland the like, followed by optionally subjecting to a surface treatment,respectively subjecting the surface-treated aluminum part material to anelectrodeposition coating, an intercoat coating and a topcoat coating,and assembling the topcoat-coated aluminum part material to theelectrodeposition-coated steel part material-assembled automobile body.

[0048] The automobile body-coating method in the second embodiment ofthe first invention is characterized in that the coating methodcomprises the following steps, a step of coating a heat-curableelectrodeposition coating composition onto an automobile body partly ortotally comprising an aluminum material, a step of coating a water basedchipping primer coating composition, a step of coating a water based orpowder intercoat coating composition, and a step of coating a curabletopcoat coating composition, that respective coating films are cured byparticular curing methods, and that the aluminum material has a degreeof surface roughness of 0.2 μm or less in terms of Ra.

[0049] The coating method in the first embodiment of the firstinvention, in the case where a sole metal base material such as analuminum material, an aluminum material-coated steel material and thelike is used as a base material of the automobile body, may be carriedout by the following methods, for example,

[0050] (1) a method which comprises subjecting the metal base materialto a press molding into a predetermined part material such as an enginehood, fender panel and the like, followed by optionally subjecting to asurface treatment, assembling the surface-treated part material to theautomobile body, respectively subjecting to an electrodepositioncoating, a water based chipping primer coating, an intercoat coating anda topcoat coating;

[0051] (2) a method which comprises subjecting the metal base materialto a press molding into a predetermined part material, followed byoptionally subjecting to a surface treatment, subjecting to anelectrodeposition coating, assembling the electrodeposition-coated partmaterial to the automobile body, respectively subjecting to a waterbased chipping primer coating, an intercoat coating and a topcoatcoating;

[0052] (3) a method which comprises subjecting the metal base materialto a press molding into a predetermined part material, followed byoptionally subjecting to a surface treatment, respectively subjecting toan electrodeposition coating, and a water based chipping primer coating,assembling a chipping primer-coated part material to the automobilebody, and respectively subjecting to an intercoat coating and a topcoatcoating;

[0053] (4) a method which comprises subjecting the metal base materialto a press molding into a predetermined part material, followed byoptionally subjecting to a surface treatment, respectively subjecting toan electrodeposition coating, a water based chipping primer coating, anintercoat coating, assembling the intercoat-coated part material to theautomobile body, and subjecting to a topcoat coating; and

[0054] (5) a method which comprises subjecting the metal base materialto a press molding into a predetermined part material, followed byoptionally subjecting to a surface treatment, respectively subjecting toan electrodeposition coating, a water based chipping primer coating, anintercoat coating and a topcoat coating, and assembling thetopcoat-coated part material to the automobile body.

[0055] The coating method in the second embodiment of the firstinvention, in the case where an aluminum material and a steelmaterial-combined metal material is used as a base material of theautomobile body, may be carried out by the following methods, forexample,

[0056] (1) a method which comprises assembling to the automobile body asurface-treated aluminum part material prepared by subjecting analuminum material to a press molding into a predetermined part materialsuch: as an engine hood, fender panel and the like followed byoptionally subjecting to a surface treatment, and a surface-treatedsteel part material prepared by subjecting a steel material to a pressmolding into a predetermined part material such as an engine hood,fender panel and the like, followed by subjecting to a surfacetreatment, followed by respectively subjecting to an electrodepositioncoating, a water based chipping primer coating, an intercoat coating anda topcoat coating;

[0057] (2) a method which comprises assembling to the automobile body anelectrodeposition-coated aluminum part material prepared by subjectingan aluminum material to a press molding into a predetermined partmaterial such as an engine hood, fender panel and the like, followed byoptionally subjecting to a surface treatment, and subjecting thesurface-treated aluminum part material to an electrodeposition coating,and an electrodeposition-coated steel part material prepared bysubjecting a steel material to a press molding into a predetermined partmaterial such as an engine hood, fender panel and the like, followed bysubjecting to a surface treatment, and subjecting to anelectrodeposition coating, followed by respectively subjecting to awater based chipping primer coating, an intercoat coating and a topcoatcoating;

[0058] (3) a method which comprises assembling to the automobile body awater based chipping primer-coated aluminum part material prepared bysubjecting an aluminum material to a press molding into a predeterminedpart material such as an engine hood, fender panel and the like,followed by optionally subjecting to a surface treatment, respectivelysubjecting the surface-treated aluminum part material to anelectrodeposition coating and a water based chipping primer coating, anda water based chipping primer-coated steel part material prepared bysubjecting a steel material to a press molding into a predetermined partmaterial such as an engine hood, fender panel and the like, followed bysubjecting to a surface treatment, and respectively subjecting thesurface-treated steel part material to an electrodeposition coating anda water based chipping primer coating, followed by respectivelysubjecting to an intercoat coating, and a topcoat coating;

[0059] (4) a method which comprises assembling an intercoat-coatedaluminum part material prepared by subjecting an aluminum material to apress molding into a predetermined part material such as an engine hood,fender panel and the like, followed by optionally subjecting to asurface treatment, and respectively subjecting the surface-treatedaluminum part material to an electrodeposition coating, a water basedchipping primer coating and an intercoat coating, and anintercoat-coated steel part material prepared by subjecting a steelmaterial to a press molding into a predetermined part material such asan engine hood, fender panel and the like, followed by subjecting to asurface treatment, and respectively subjecting the surface-treated steelpart material to an electrodeposition coating, a water based chippingprimer coating and an intercoat coating, followed by subjecting to atopcoat coating;

[0060] (5) a method which comprises assembling to the automobile body atopcoat-coated aluminum part material prepared by subjecting an aluminummaterial to a press molding into a predetermined part material such asan engine hood, fender panel and the like, followed by optionallysubjecting to a surface treatment, and respectively subjecting thesurface-treated aluminum part material to an electrodeposition coating,a water based chipping primer coating, an intercoat coating and atopcoat coating, and a topcoat-coated steel part material prepared bysubjecting a steel material to a press molding into a predetermined partmaterial such as an engine hood, fender panel and the like, followed bysubjecting to a surface treatment, and respectively subjecting thesurface-treated steel part material to an electrodeposition coating, awater based chipping primer coating, an intercoat coating and a topcoatcoating.

[0061] In addition to the above methods, for example, orders ofrespective coating steps of the aluminum material and the steel materialmay be varied. Specifically, a steel material maybe subjected to a pressmolding into a predetermined part material such as an engine hood,fender panel and the like, followed by assembling the steel partmaterial to the automobile body, and respectively subjecting to asurface treatment and an electrodeposition coating to prepare anelectrodeposition-coated steel part material-assembled automobile body.

[0062] Separately, an aluminum material is subjected to a press moldinginto a predetermined part material such as an engine hood, fender paneland the like, followed by optionally subjecting to a surface treatment,respectively subjecting the surface-treated aluminum part material to anelectrodeposition coating, a water based chipping primer coating, anintercoat coating and a topcoat coating, and assembling thetopcoat-coated aluminum part material to the electrodeposition-coatedsteel part material-assembled automobile body.

[0063] The above heat-curing means curing at a curing-temperature whereheat-curable. The above setting or predrying means drying underessentially non-curable conditions when heat-curable. In the topcoatcoating composition, in the case where an actinic ray-curable topcoatcoating composition is used, the meaning of heat-curing may be replacedwith a meaning of irradiation of actinic rays for explanation. The term4C4B represented in the coating method means 4 coating steps and 4curing steps.

[0064] The automobile body-coating method in the third embodiment of thefirst invention is characterized in that the coating method comprisesthe following steps, a step of coating a heat-curable electrodepositioncoating composition onto an automobile body partly or totally comprisingan aluminum material, a step of coating a water based chipping primercoating composition, and a step of coating a curable topcoat coatingcomposition, that respective coating films are cured by particularcuring methods, and that the aluminum material has a degree of surfaceroughness of 0.2 μm or less in terms of Ra.

[0065] The coating method in the third embodiment of the firstinvention, in the case where a sole metal base material such as analuminum material, an aluminum material-coated steel material and thelike is used as a base material of the automobile body, may be carriedout by the following methods, for example,

[0066] (1) a method which comprises subjecting the metal base materialto a press molding into a predetermined part material such as an enginehood, fender panel and the like, followed by optionally subjecting to asurface treatment, assembling the surface-treated part material to theautomobile body, respectively subjecting to an electrodepositioncoating, a water based chipping primer coating, and a topcoat coating;

[0067] (2) a method which comprises subjecting the metal base materialto a press molding into a predetermined part material, followed byoptionally subjecting to a surface treatment, subjecting to anelectrodeposition coating, assembling the electrodeposition-coated partmaterial to the automobile body, respectively subjecting to a waterbased chipping primer coating, and a topcoat coating;

[0068] (3) a method which comprises subjecting the metal base materialto a press molding into a predetermined part material, followed byoptionally subjecting to a surface treatment, respectively subjecting toan electrodeposition coating, and a water based chipping primer coating,assembling a chipping primer-coated part material to the automobilebody, and subjecting to a topcoat coating;

[0069] (4) a method which comprises subjecting the metal base materialto a press molding into a predetermined part material, followed byoptionally subjecting to a surface treatment, respectively subjecting toan electrodeposition coating, a water based chipping primer coating, anintercoat coating, assembling the intercoat-coated part material to theautomobile body, and subjecting to a topcoat coating; and

[0070] (5) a method which comprises subjecting the metal base materialto a press molding into a predetermined-part material, followed byoptionally subjecting to a surface treatment, respectively subjecting toan electrodeposition coating, a water based chipping primer coating, anda topcoat coating, and assembling the topcoat-coated part material tothe automobile body.

[0071] The coating method in th(e third embodiment of the firstinvention, in the case where an aluminum material and a steelmaterial-combined metal material is used as a base material of theautomobile body, may be carried out by the following methods, forexample,

[0072] (1) a method which comprises assembling to the automobile body asurface-treated aluminum part material prepared by subjecting analuminum material to a press molding into a predetermined part materialsuch as an engine hood, fender panel and the like followed by optionallysubjecting to a surface treatment, and a surface-treated steel partmaterial prepared by subjecting a steel material to a press molding intoa predetermined part material such as an engine hood, fender panel andthe like, followed by subjecting to a surface treatment, followed byrespectively subjecting to an electrodeposition coating, a water basedchipping primer coating, a water based chipping primer coating, and atopcoat coating;

[0073] (2) a method which comprises assembling to the automobile body anelectrodeposition-coated aluminum part material prepared by subjectingan aluminum material to a press molding into a predetermined partmaterial such as an engine hood, fender panel and the like, followed byoptionally subjecting to a surface treatment, and subjecting thesurface-treated aluminum part material to an electrodeposition coating,and an electrodeposition-coated steel part material prepared bysubjecting a steel material to a press molding into a predetermined partmaterial such as an engine hood, fender panel and the like, followed bysubjecting to a surface treatment, and subjecting to anelectrodeposition coating, followed by respectively subjecting to awater based chipping primer coating, and a topcoat coating;

[0074] (3) a method which comprises assembling to the automobile body awater based chipping primer-coated aluminum part material prepared bysubjecting an aluminum material to a press molding into a predeterminedpart material such as an engine hood, fender panel and the like,followed by optionally subjecting to a surface treatment, respectivelysubjecting the surface-treated aluminum part material to anelectrodeposition coating and a water based chipping primer coating, anda water based chipping primer-coated steel part material prepared bysubjecting a steel material to a press molding into a predetermined partmaterial such as an engine hood, fender panel and the like, followed bysubjecting to a surface treatment, and respectively subjecting thesurface-treated steel part material to an electrodeposition coating anda water based chipping primer coating, followed by subjecting to atopcoat coating; and

[0075] (4) a method which comprises assembling to the automobile body atopcoat-coated aluminum part material prepared by subjecting an aluminummaterial to a press molding into a predetermined part material such asan engine hood, fender panel and the like, followed by optionallysubjecting to a surface treatment, and respectively subjecting thesurface-treated aluminum part material to an electrodeposition coating,a water based chipping primer coating, and a topcoat coating, and atopcoat-coated steel part material prepared by subjecting a steelmaterial to a press molding into a predetermined part material such asan engine hood, fender panel and the like, followed by subjecting to asurface treatment, and respectively subjecting the surface-treated steelpart material to an electrodeposition coating, a water based chippingprimer coating, aid a topcoat coating.

[0076] In addition to the above methods, for example, orders ofrespective coating steps of the aluminum material and the steel materialmay be varied. Specifically, a steel material may be subjected to apress molding into a predetermined part material such as an engine hood,fender panel and the like, followed by assembling the steel partmaterial to the automobile body, and respectively subjecting to asurface treatment and an electrodeposition coating to prepare anelectrodeposition-coated steel part material-assembled automobile body.

[0077] Separately, an aluminum material is subjected to a press moldinginto a predetermined part material such as an engine hood, fender paneland the like, followed by optionally subjecting to a surface treatment,respectively subjecting the surface-treated aluminum part material to anelectrodeposition coating, a water based chipping primer coating, and atopcoat coating, and assembling the topcoat-coated aluminum partmaterial to the electrodeposition-coated steel part material-assembledautomobile body.

[0078] The second invention in a first embodiment provides an automobilebody-coating method for coating an outer plate area and/or an innerplate area of an automobile body comprising an oxidized aluminummaterial or an oxidized aluminum material and steel material-combinedmetal material, which method comprises (1) electrodeposition coating aheat-curable electrodeposition coating composition onto the surface ofthe oxidized aluminum material in the outer plate area and/or the innerplate area of the automobile body to form an electrodeposition coatingfilm followed by heat curing, optionally the steel material beingsubjected to a surface treatment followed by being subjected to anelectrodeposition coating.

[0079] The second invention in a second embodiment provides anautomobile body-coating method for coating an outer plate area and/or aninner plate area of an automobile body comprising an oxidized aluminummaterial or an oxidized aluminum material and steel material-combinedmetal material, which method comprises (2) coating a heat-curable waterbased intercoat coating composition or a heat-curable intercoat powdercoating composition onto the outer plate area and/or the inner platearea of the automobile body to form a water based intercoat coating filmor an intercoat powder coating film respectively followed by creating acurable topcoat coating composition to form a curable topcoat coatingfilm, and heat curing both coating films independently from each otheror simultaneously, optionally the steel material being subjected to anelectrodeposition coating.

[0080] The automobile body-coating method in the first embodiment of thesecond invention is characterized in that a heat-curableelectrodeposition coating film is formed onto the surface of an oxidizedaluminum material in the automobile body partly or totally comprisingthe oxidized aluminum material, and that a particular aluminum materialis used as the oxidized aluminum material.

[0081] The coating method in the first embodiment of the secondinvention, in the case where an oxidized aluminum material is used as abase material of the automobile body, may be carried out by thefollowing methods; for example,

[0082] (1) a method which comprises subjecting the metal material to apress molding into a predetermined part material such as an engine hood,fender panel and the like, followed by subjecting to an oxidizingsurface treatment, assembling the oxidizing surface-treated partmaterial to the automobile body, and subjecting to an electrodepositioncoating; and

[0083] (2) a method which comprises subjecting the metal base materialto a press molding into a predetermined part material, followed bysubjecting to an oxidizing surface treatment, subjecting to anelectrodeposition coatings and assembling the electrodeposition-coatedpart material to the automobile body.

[0084] The coating method in the first embodiment of the secondinvention, in the case where an oxidized aluminum and a steelmaterial-combined metal material is used as a base material of theautomobile body, may be carried out by the following methods; forexample,

[0085] (1) a method which comprises assembling to the automobile body anoxidized aluminum part material prepared by subjecting an aluminummaterial to a press mold into a predetermined part material such as anengine hood, fender panel and the like, followed by subjecting to anoxidizing surface treatment, and a surface-treated steel part materialprepared by subjecting a steel material to a press molding into apredetermined part material such as an engine hood, fender panel and thelike, followed by subjecting to a surface treatment, and followed bysubjecting to an electrodeposition coating; and

[0086] (2) a method which comprises assembling an electrodepositioncoated aluminum part material prepared by subjecting an aluminummaterial to a press molding into a predetermined part material such asan engine hood, fender, panel and the like, followed by subjecting to anoxidizing surface treatment, and subjecting the oxidized aluminum partmaterial to an electrodeposition coating, and an electrodepositioncoated steel part material prepared by subjecting a steel material to apress molding into a predetermined part material such as an engine hood,fender panel and the like, followed by subjecting to a surface treatmentand subjecting the surface-treated steel part material to anelectrodeposition coating.

[0087] Optionally, a chipping primer coating film such as a barriercoating film, an intercoat cured coating film and a topcoat curedcoating film as known in the field of the automobile coating compositionmay successively be formed onto the surface of the aboveelectrodeposition coating film.

[0088] The oxidized aluminum material may include ones prepared bysubjecting an aluminum material known in the art to a chemical surfacetreatment on an anodizing surface treatment.

[0089] The automobile body-coating method in the second embodiment ofthe second invention is characterized in that the coating methodcomprises coating onto an automobile body partly or totally comprisingan aluminum material a water based or powder intercoat coatingcomposition, followed by coating a curable topcoat coating composition,that respective coating films are cured by a particular curing method,that an oxidized aluminum material having a degree of surface roughnessof 0.2 μm or less in terms of Ra is used as the aluminum material.

[0090] The coating method in the second embodiment of the secondinvention, in the case where an oxidized aluminum material is used as abase material of the automobile body, may be carried out by thefollowing methods; for example,

[0091] (1) a method which comprises subjecting the metal material to apress molding into a predetermined part material such as an engine hood,fender panel and the like, followed by subjecting to an oxidizingsurface treatment, assembling the oxidizing part material to theautomobile body, respectively subjecting to an intercoat coating and atopcoat coating;

[0092] (2) a method which comprises subjecting the metal base materialto a press molding into a predetermined part material such as an enginehood, fender panel and the like, followed by subjecting to an oxidizingsurface treatment, subjecting the oxidized part material to an intercoatcoating, assembling the intercoat-coated part material to the automobilebody, and subjecting to a topcoat coating; and

[0093] (3) a method which comprises subjecting the metal base materialto a press molding into a predetermined part material such as an enginehood, fender panel and the like, followed by subjecting to an oxidizingsurface treatment, subjecting the oxidized part material to an intercoatcoating, subjecting to a topcoating, and assembling the topcoated partmaterial to the automobile body.

[0094] The coating method in the second embodiment of the secondinvention, in the case where an aluminum and a steel material-combinedmetal material is used as a base material of the automobile body, may becarried out by the following methods; for example,

[0095] (1) a method which comprises assembling to the automobile body anoxidized aluminum part material prepared by subjecting the aluminummaterial to a press molding into a predetermined part material such asan engine hood, fender panel and the like, followed by subjecting to anoxidizing surface treatment, and a surface-treated steel part materialprepared by subjecting the steel material to a press molding into apredetermined part material such as an engine hood, fender panel and thelike, followed by subjecting to a surface treatment, respectivelysubjecting to an intercoat coating and a topcoat coating;

[0096] (2) a method which comprises assembling to the automobile body anintercoat-coated aluminum part material prepared by subjecting thealuminum material to a press molding into a predetermined part materialsuch as an engine hood, fender panel and the-like, followed bysubjecting to an oxidizing surface treatment, subjecting the oxidizedaluminum part material to an intercoat coating, and an intercoat-coatedsteel part material prepared by subjecting the steel material to a pressmolding into a predetermined part material such as an engine hood,fender panel and the like, followed by subjecting to a surfacetreatment, subjecting the surface-treated steel part material to anelectrodeposition coating, an intercoat coating, and subjecting to atopcoat coating; and

[0097] (3) a method which comprises assembling to the automobile body atopcoat-coated aluminum part material prepared by subjecting thealuminum material to a press molding into a predetermined part materialsuch as an engine hood, fender panel and the like, followed bysubjecting to an oxidizing surface treatment, subjecting the oxidizedaluminum part material to an intercoat coating and subjecting to atopcoat coating, and a topcoat-coated steel part material prepared bysubjecting the steel material to a press molding into a predeterminedpart material such as an engine hood, fender panel and the like,followed by subjecting to a surface treatment, respectively subjectingthe oxidized aluminum part material to an electrodeposition coating, anintercoat coating and a topcoat coating.

[0098] In addition to the above methods, for example, orders ofrespective coating steps of the aluminum material and the steel materialmay be varied. Specifically, a steel material may be subjected to apress molding into a predetermined part material such as an engine hood,fender panel and the like, followed by assembling the steel partmaterial to the automobile body, and respectively subjecting to asurface treatment and an electrodeposition coating to prepare anelectrodeposition-coated steel part material-assembled automobile body.

[0099] Separately, an aluminum material is subjected to a press moldinginto a predetermined part material such as an engine hood, render paneland the like, followed by optionally subjecting to an oxidizing surfacetreatment, respectively subjecting the surface-treated aluminum partmaterial to an intercoat coating and a topcoat coating, and assemblingthe topcoat-coated aluminum part material to theelectrodeposition-coated steel part material-assembled automobile body.

[0100] Optionally, a chipping primer coating film such as a barriercoating film as known in the field of the automobile coating compositionmay be formed onto the surface of the above oxidized coating film.

[0101] The oxidized aluminum material may include ones prepared bysubjecting an aluminum material known in the art to a chemical surfacetreatment or an anodizing surface treatment.

[0102] The coating method of the third invention is characterized inthat the coating method relates to a method which comprises applying afilm facing material to the automobile body partly or totally comprisingan aluminum material, and that the aluminum material has a degree ofsurface roughness of 0.2 μm or less in terms of Ra.

[0103] The aluminum material used in the present invention may includeones used in the field of the automobile body without particularlimitations, specifically may include an aluminum alloy base materialsuch as a JIS A5000 series aluminum alloy plate containing magnesium, aJIS A6000 series aluminum alloy base material containing magnesium andsilica, and the like.

[0104] In the present invention, of these aluminum alloy base materials,the JIS A6000 series aluminum alloy base material is particularlypreferable in that more than once heat-curing of a coating compositionat a temperature of 140° C. or higher may impart strength and hardnessto the coating film due to the metals contained therein. A content orthe metals may preferably be in the range of 0.5 to 3% by weight.

[0105] The aluminum material preferably has a degree of surfaceroughness as measured by use of a JIS B0601 three dimensional degree ofroughness meter in the range of 0.2 μm or less, particularly 0.1 μm orless in terms of Ra. A Ra more than 0.2 μm may reduce smoothness of anelectrodeposition coating film formed onto the aluminum material,resulting in reducing smoothness of a topcoat coating film and reducinggloss of a finished coating film. On the other hand, a Ra less than 0.01μm may result poor adhesion properties between a cationicelectrodeposition coating film and the aluminum material. The degree ofsurface roughness of the aluminum material may be controlled by acontrol of a degree of roughness of a roll on rolling and by a surfacetreatment technique such as a mechanical polishing, chemical polishing,electropolishing, and the like. Of these, the electropolishing ispreferable because of making easily possible a polishing with a fineroughness.

[0106] The aluminum-coated steel material in the first and thirdinvention may include, for example, an aluminum-electroplated steelplate, a molten aluminum-coated steel plate and the like.

[0107] The surface treatment of the aluminum material and thealuminum-coated steel material may be carried out by the conventionalsurface treatment.

[0108] In the case where the anodizing treatment is not carried out, thesurface treatment may be carried out by the following steps (1) to (3):

[0109] (1) pretreatment: aluminum material-mechanicalpolishing-degreasing (acid, acid salt, alkali, alkali salt, organicsolvent, surface active agent, electrodegreasing, etc.)—washing withwater (including neutralization)—chemical polishing—washing with water;

[0110] (2) chemical surface treatment: A surface treating agent used inthe chemical surface treatment may include, for example, a phosphatebased treating agent (albond method, zinc phosphate, iron phosphate,manganese phosphate), alcohol phosphate based treating agent, phosphatechromate based treating agent, sodium carbonate based treating agent,chromate based treating agent (chromate, bichromate), vamite process(treatment by use of a steam at 120 to 150° C., treatment by distilledwater at 100° C., treatment by an amine-containing distilled water at100° C.), titanium based surface treating agent, fluorine based surfacetreating agent, and the like. The surface treating agent may alsoinclude an etching agent (inorganic acid, organic acid, salts thereof),heavy metals (Zr, Mo, W, Ti, tn, Zn, Ni, etc.), salts thereof (nitricacid, phosphoric acid, hydrofluoric acid, etc), and a surface treatingagent using organic and/or inorganic weakly basic or weakly acidicsubstances prepared optionally by adding a binder (phenol resin,carboxylized polyolefin based resin, etc.), anticorrosive agent(vanadate, organosulfonic acid, gallic acid based compound, sulfide,triazinethiol, benzotriazole, thiocarbonyl compound, etc.),adhesion-imparting agent (silane coupling agent, silica gel, aerosil,etc.) and the like.

[0111] Of these, the treatment by use of the zinc phosphate treatingagent is preferable, which treating agent is such that a compound suchas phosphoric acid, zinc acid phosphate, potassium fluoride and the likeis used as a starting material, that the treating agent is brought intocontact with the aluminum material so that etching of the aluminum maytake place and the eluted aluminum may be reacted with phosphoric acidand fluoric acid to form an aluminum salt, and that the zinc acidphosphate (zinc 2-hydrogen phosphate) may be reacted with aluminum andfluoric acid to form zinc 3-hydrogen phosphate, which deposits on thesurface of the aluminum material to form a film.

[0112] (3) post-treatment: washing with water—drying.

[0113] In the case where the anodizing treatment is carried out, thesurface treatment of the aluminum material may be carried out by thefollowing steps {circle over (1)} to {circle over (3)}:

[0114] {circle over (1)} degreasing—alkali etching—desmat—anodizingtreatment—sealing treatment,

[0115] {circle over (2)} degreasing—alkali etching—desmat—anodizingtreatment—secondary electrolytic coloring,

[0116] {circle over (3)} degreasing—polishing (electropolishing,chemical polishing, matte finish, etc.)—anodizing treatment—(optionallydying).

[0117] Respective steps may include a step of washing with water.

[0118] The anodizing treatment may include, for example, a sulfuric acidprocess, oxalic aced process, chromic acid process, boric acid processand the like. Of these, the sulfuric acid process is preferable in thata coating film showing good properties in rigidity and corrosionresistance can be formed. The step {circle over (3)} is preferable inthat a coating film showing good finish appearance can be obtained.

[0119] In the case of the anodized aluminum material, an anionicelectrodeposition coating may particularly be carried out in that thealuminum material may show good properties in durability and finishappearance.

[0120] The oxidizing treatment of the aluminum material in the secondinvention may include any surface treatments known in the art,specifically a chemical surface treatment, anodizing treatment and thelike.

[0121] The chemical surface treatment may be carried out by thefollowing steps (1) to (3):

[0122] (1) pretreatment: aluminum material-mechanicalpolishing—degreasing (acid, acid salt, alkali, alkali salt, organicsolvent, surface active agent, electrodegreasing, etc.)—washing withwater (including neutralization)—chemical polishing—washing with water;

[0123] (2) chemical surface treatment: A surface treating agent used inthe chemical surface treatment may include, for example, a phosphatebased treating agent (albond method, zinc phosphate, iron phosphate,manganese phosphate), alcohol phosphate based treating agent, phosphatechromate based treating agent, sodium carbonate based treating agent,chromate based treating agent (chromate, bichromate), vamite process(treatment by use of a steam at 120 to 150° C., treatment by distilledwater at 100° C., treatment by an amine-containing distilled water at100° C.), titanium based surface treating agent, fluorine based surfacetreating agent, and the like.

[0124] Of these, the treatment by use of the zinc phosphate treatingagent is preferable, which treating agent is such that a compound suchas phosphoric acid, zinc acid phosphate, potassium fluoride and the likeis used as a starting material, that the treating agent is brought intocontact with the aluminum material so that etching of the aluminum maytake place and the eluted aluminum may be reacted with phosphoric acidand fluoric acid to form an aluminum salt, and that the zinc acidphosphate (zinc 2-hydrogen phosphate) may be reacted with aluminum andfluoric acid to form zinc 3-hydrogen phosphate, which deposits on thesurface of the aluminum material to form a film.

[0125] (3) post-treatment: washing with water—drying.

[0126] A coloring method in the chemical surface treatment may include,for example, a method of coloring by a treating solution used in thechemical surface treatment, a method of coloring by adding a metal saltto the treating solution, a method of coloring by a complex compound ofpotassium permanganate, cobalt, copper, potassium ferrocyanide, iron andthe like, alizarium coloring agent, and the like.

[0127] In the case of the chemical surface-treated aluminum material, acationic electrodeposition coating and an anionic electrodepositioncoating can be carried out, but the cationic electrodeposition coatingis preferably carried out in that the oxidized aluminum material showsgood properties in durability and finish appearance.

[0128] The anodizing treatment may be carried out by the following steps{circle over (1)} to {circle over (3)}:

[0129] {circle over (1)} degreasing—alkali etching—desmat—anodizingtreatment—sealing treatment,

[0130] {circle over (2)} degreasing—alkali etching—desmat—anodizingtreatment—secondary electrolytic coloring,

[0131] {circle over (3)} degreasing—polishing (electropolishing,chemical polishing, matte finish, etc.)—anodizing treatment—(optionallydying).

[0132] Respective steps may include a step of washing with water.

[0133] The anodizing treatment may include, for example, a sulfuric acidprocess, oxalic acid process, chromic acid process, boric acid processand the like. Of these, the sulfuric acid process is preferable in thata coating film showing good properties in rigidity and corrosionresistance can be formed. The step {circle over (3)} is preferable inthat a coating film showing good finish appearance can be obtained.

[0134] In the case of the anodized aluminum material, an anionicelectrodeposition coating may particularly be carried out in that thealuminum material may show good properties in durability and finishappearance.

[0135] The anodized film may optionally be colored by a natural colordevelopment and an electrolytic coloring A colored film-formed coloredanodized aluminum material may be used. Coloring of the film by thenatural color development and electrolytic coloring may be carried outby the coloring technique known in the art A film-forming method by theelectrolytic coloring may include a method which comprises carrying outan anodizing treatment, followed by carrying out a secondaryelectrolysis in an electrolyte containing a metal salt, for coloring, ora method which comprises adding a metal salt into an electrolyte foranodizing, followed by carrying out an anodizing treatment and coloringsimultaneously. The metal salt may include, for example, nickel salt,copper salt, tin salt, cobalt salt, lead salt, manganese salt, goldsalt, silver salt, molybdenum salt, selenium salt and the like. The saltmay include a salt of an inorganic acid such as sulfuric acid, a salt ofan organic acid such as acetic acid, and a salt of an oxyacid, and thelike.

[0136] The surface treating agent may also include an etching agent(inorganic acid, organic acid, salts thereof), heavy metals (Zr, Mc, W,Ti, Mn, Zn, Ni, etc.), salts thereof (nitric acid, phosphoric acid,hydrofluoric acid, etc.), and a surface treating agent using organicand/or inorganic weakly basic or weakly acidic substances preparedoptionally by adding a binder (phenol resin, carboxylized polyolefinbased resin, etc.), anticorrosive agent (vanadate, organosulfonic acid,gallic acid based compound, sulfide, triazinethiol, benzotriazole,thiocarbonyl compound, etc.), adhesion-imparting agent (silane couplingagent, silica gel, aerosil, etc.) and the like.

[0137] The steel material used in combination with the aluminum materialor the oxidized aluminum material may include a steel plate used in theautomobile as known in the art, specifically a steel plate such as asteel plate, molten zinc-plated steel plate, zinc electroplated steelplate and the like, a treated steel plate subjected to a surfacetreatment such as a zinc phosphate treatment, iron phosphate treatmentand the like. In the case where the steel plate is used, the cationicelectrodeposition coating may preferably be carried out in that acoating film showing good properties in corrosion resistance,fabricating properties, finish properties, and the like can be formed.

[0138] In the present invention, formation of a heat-curableelectrodeposition coating film and the following heat-curing may becarried out by use of a cationic electrodeposition coating compositionor an anionic electrodeposition coating composition as follows.

[0139] The cationic electrodeposition coating composition may include aknown cationic electrodeposition coating composition prepared by mixinga cationic resin composition with water for dispersing. The cationicresin composition may preferably include, for example, a compositioncontaining a base resin having hydroxyl group and a cationic group, anda crosslinking agent such as a blocked polyisocyanate compound. The baseresin may include, for example, a reaction product of an epoxy resinwith a cationizing agent, one prepared by protonizing a polycondensationproduct (see U.S. Pat. No. 2,450,940) of polycarboxylic acid with apolyamine, with an acid, one prepared by protonizing a polyadduct ofpolyisocyanate compound and polyol, and mono or poly-amine with an acid,one prepared by protonizing a copolymer of hydroxyl group and aminogroup-containing acrylic or vinyl monomers with an acid (see JapanesePatent Publication No. 12395/70, Japanese Patent Publication No.12396/70), one prepared by protonizing an adduct of a polycarboxylicacid resin and an alkyleneimine with an acid (see U.S. Pat. No.3,403,088), and the like.

[0140] The cationic electrodeposition coating composition may also beobtained by neutralizing the cationic resin with an acid neutralizingagent such as acetic acid, hydroxyacetic acid and the like, followed bydispersing into water.

[0141] The anionic electrodeposition coating composition may include anacrylic resin anionic electrodeposition coating composition, polyesterresin anionic electrodeposition coating composition and the like.

[0142] The acrylic resin anionic electrodeposition coating compositionmay include, for example, one prepared by adding a curing agent such asa blocked polyisocyanate, melamine resin, urea resin and the like to ahydroxyl group and carboxyl group-containing acrylic resin, followed byneutralizing with a basic compound such as amine, and dispersing intowater.

[0143] The acrylic resin may be obtained by subjecting a monomer mixtureof a hydroxyl group-containing (meth)acrylic monomer, α,β-ethylenicallyunsaturated carboxylic acid, and optionally other radicallycopolymerizable monomer to a radical copolymerization reaction. Theradical copolymerization reaction may be carried out by the knownmethod, for example, a solution polymerization method. Theα,β-ethylenically unsaturated carboxylic acid may include, for example,(meth)acrylic acid, maleic acid and the like. The hydroxylgroup-containing (meth)acrylic monomer and other radicallycopolymerizable monomer may include the same ones as above.

[0144] The acrylic resin usually has a hydroxy value in the range of 10to 300 mg KOH/g, preferably 20 to 200 mg KOH/g, an acid value in therange of 20 to 200 mg KOH/g, preferably 30 to 100 ng KOH/g, and a numberaverage molecular weight in the range of 2,000 to 100,000, preferably3,000 to 50,000.

[0145] A mixing ratio of the base resin to the curing agent is such thatthe curing agent is in the range of 30 to 100 parts by weight,preferably 40 to 80 parts by weight per 100 parts by weight of the baseresin.

[0146] The cationic and anionic electrodeposition coating compositionsmay contain, in addition to the above-mentioned component, optionally asurface active agent, surface-controlling agent, curing agent,ultraviolet light absorber, ultraviolet light stabilizer, coloring agentand other additives.

[0147] The cationic electrodeposition coating composition is controlledso that the solid content may be in the range of about 5 to 40% byweight, and that the pH may be in the range of 5 to 9.

[0148] The anionic electrodeposition coating composition is controlledso that the solid content may be in the range of about 5 to 25% byweight, and that the pH may be in the range of 7 to 10.

[0149] An electrodeposition coating by use of the anionic or cationicelectrodeposition coating composition may be carried out by energizingbetween an electrical pole and a coating substrate in anelectrodeposition bath containing the electrodeposition coatingcomposition under the conditions of a bath temperature of 15 to 35*C anda loading voltage of 100 to 400 V.

[0150] After the completion of the above electrodeposition coating,optionally washing with a water such as an ultrafiltration filtrate (UFfiltrate), RO permeated water, industrial water, deionized water and thelike may be carried out so that the electrodeposition coatingcomposition in an excess amount may not remain on the surface of acoating product.

[0151] The predrying of the electrodeposition coating film may becarried out to such an extent that coating film drawbacks such asbubbling, sagging, pinholes and the like may not develop duringheat-curing thereof along with an intercoat coating film, specificallyby drying at a surface temperature of a coating substrate in the rangeof 10 to 80° C. for one minute to 60 minutes, preferably 2 minutes to 30minutes.

[0152] The electrodeposition coating film may be heat-cured at a surfacetemperature of a coating substrate of 110 to 200° C., preferably 140 to180° C., for 10 to 180 minutes, preferably 20 to 50 minutes.

[0153] In the first embodiment of the first invention, a heat-curablewater based intercoat coating composition or a heat-curable powderintercoat coating composition may be coated onto the electrodepositioncoating film so as to improve smoothness, definition properties,interlayer adhesion properties, anti-chipping properties and the like.

[0154] The intercoat coating composition may include ones known in theart, for example, ones prepared by mixing a base resin such as acrylicresin, polyester resin, alkyd resin and the like, a curing agent such asmelamine resin, blocked polyisocyanate compound, polyhydrazide compound,polyepoxide, polycarboxylic acid (or anhydride thereof),hydroxyalkylamide compound and the like, a color pigment, an extenderpigment, and the like. The water based intercoat coating composition maybe coated by air spray coating, airless spray coating, electrostaticcoating and the like so as to be a cured film thickness in the range of10 to 40 μm. The powder intercoat coating composition may be coated byan electrostatic spray coating such as a corona discharge coating,frictional electrification coating and the like, so as to be a curedfilm thickness in the range of 30 to 80 μm.

[0155] The predrying of the water based intercoat coating film may becarried out to such an extent that coating film drawbacks such asbubbling, sagging, pinholes and the like may not develop duringheat-curing thereof along with an electrodeposition coating film and atopcoat coating film, specifically by drying at a surface temperature ofa coating substrate in the range of 10 to 80° C. for one minute to 60minutes, preferably 2 minutes to 30 minutes.

[0156] The water based intercoat coating film may be heat-cured at asurface temperature of a coating substrate of 110° C. to 200° C.,preferably 140 to 180° C. for 10 to 180 minutes, preferably 20 to 50minutes.

[0157] The predrying of the powder intercoat coating film may be carriedout to such an extent powder particles may not weld together so as notto fall off while being transported by a conveyor or so, and thatimigration of the electrodeposition coating composition and the topcoatcoating composition may not take place so as not to adversely effect oncoating film appearance and coating film performances, specifically bydrying at a surface temperature of a coating substrate in the range of40 to 100*C for one minute to 60 minutes, preferably 2 minutes to 30minutes.

[0158] The powder intercoat coating film may be heat-cured at a surfacetemperature of a coating substrate of 140 to 200° C., preferably 150 to180° C., for 10 to 180 minutes, preferably 20 to 50 minutes.

[0159] The heat-curable topcoat coating composition to be coated ontothe intercoat coating film may include ones imparting a fine appearanceto the coating substrate, specifically may include any coatingcompositions known in the art and capable of forming a coating filmshowing good properties in finish appearance such as definitionproperties, smoothness, gloss and the like, weather resistance such asgloss retention properties, color retention properties, chalkingresistance and the like, chemical resistance, water resistance, moistureresistance, curing properties and the like, for example, liquid coatingcompositions such as an organic solvent based, water based, powdercoating composition, water dispersion based, non-water dispersion typeand the like prepared by dissolving or dispersing into water or anorganic solvent a heat-curable resin composition, as a vehicle maincomponent, containing a base resin such as acrylic resin, polyesterresin, silicone resin, fluorocarbon resin, alkyd resin and the like, anda curing agent such as melamine resin, blocked polyisocyanate compound,polyhydrazide compound, polyepoxide, polycarboxylic acid (or anhydridethereof), hydroxyalkylamide compound and the like, and a powder coatingcomposition. Of these, a heat-curable topcoat coating compositioncontaining a heat-curable resin composition, as the vehicle maincomponent, such as an amino resin-curing acrylic resin, aminoresin-curing alkyd resin, amino resin-curing polyester resin, acid (oranhydride thereof)-curing epoxy group-containing acrylic resin,silicone-curing acrylic resin and the like.

[0160] The topcoat coating composition may be classified to an enamelcoating composition prepared by adding a pigment such as metallicpigment, pearl pigment, color pigment and the like to the coatingcomposition containing the vehicle main component, and a clear coatingcomposition free of the above pigments.

[0161] A method of forming a topcoat coating film by use of the abovecoating composition may include the following methods {circle over (1)}to {circle over (3)}:

[0162] {circle over (1)} a method which comprises coating a metalliccoating composition containing a metallic pigment, pearl pigment,optionally color pigment, or a solid color coating compositioncontaining a color pigment, followed by heat curing (metallic finish,pearl finish, solid color finish by one coat one bake coating method);

[0163] {circle over (2)} a method which comprises coating a metallicpigment-containing metallic coating composition, a pearlpigment-containing coating composition or a solid color coatingcomposition, followed by heat curing, coating a clear coatingcomposition, and heat-curing (metallic finish, pearl finish or solidcolor finish by 2 coats 2 bakes coating method); and

[0164] {circle over (3)} a method which comprises coating a metalliccoating composition, pearl pigment-containing coating composition or asolid color coating composition, followed by coating a clear coatingcomposition, and heat curing both coating films simultaneously (metallicfinish, pearl finish or solid color finish).

[0165] The above topcoat coating compositions may preferably be coatedby a spray coating method, an electrostatic coating method and the like,so as to be a dry film thickness in the range of 25 to 40 μm in the caseof the method {circle over (1)}, in the cases of the methods {circleover (2)} and {circle over (3)}, in the range of 10 to 30 μm in the caseof the metallic coating composition, pearl pigment-containing coatingcomposition and the solid color coating composition, and in the range of25 to 50 μm in the case of the clear coating composition. Heatingconditions may arbitrarily be selected depending on the vehiclecomponent and are ones of 80 to 170° C., particularly 120 to 150° C.,for 10 to 40 minutes.

[0166] The clear coating composition may include an actinic ray-curabletopcoat coating composition prepared by optionally adding aphotopolymerization initiator, photosensitizer, polymerizable diluentand the like to acrylic resin containing a polymerizable functionalgroup such as acryloyl group, methacryloyl group, vinyl group and thelike as crosslinkable by light such as ultraviolet light, sunlight andthe like, silicone-resin and fluorocarbon resin. A light source used inthe actinic ray-curable topcoat coating composition may include, forexample, ultrahigh pressure, high pressure, medium pressure or lowpressure mercury lamp, chemical lamp, carbon arc lamp, xenone lamp,metal halide lamp, tungsten lamp and the like. An irradiation-dose isusually in the range of 10 to 500 mJ/cm².

[0167] In the second embodiment of the first invention, a water basedchipping primer coating composition may be coated onto theelectrodeposition coating film for the purpose of improving smoothness,definition properties, interlayer adhesion properties, anti-chippingproperties and the like.

[0168] The term “a water based chipping primer coating composition” maynot conventionally be used, but in the present invention, a water basedcoating composition having the above-mentioned characteristic values andcapable of forming a coating film achievable the purpose of the presentinvention may be called as “a water based chipping primer coatingcomposition”.

[0169] The chipping primer coating composition is characterized by beingcoated onto the surface; of an electrodeposition coating film prior tocoating an intercoat coating composition in the coating steps of coatingthe electrodeposition coating composition onto the steel material,followed by coating the intercoat coating composition, and coating thetopcoat coating composition, resulting in making it possible to obtain acoating film showing excellent properties in anti-chipping properties,corrosion resistance, physical performances and the like.

[0170] A water based chipping primer coating film controlled at a staticglass transition temperature in the range of 0 (zero) to −75° C. (morepreferably as explained later, controlled at a tensile elongation atbreak at −20° C. of the coating film in the range of 200 to 1000%measured at a tensile speed of 20 mm/min.) is more flexible comparedwith the intercoat coating film used for the purpose of improvinganti-chipping properties, resulting in that application of a strongimpact force due to collision of rock salt, gravel and the like onto thesurface of a multi-layer coating film comprising the water basedchipping primer coating film having the above physical properties, theintercoat coating film and topcoat coating film may result that all oralmost all of the impact energy may be absorbed into the water basedchipping primer coating film without reaching the electrodepositioncoating film underneath, and that both the intercoat coating film andtopcoat coating film are subjected to almost no physical damage, thatis, the water based chipping primer coating film shows a shock-absorbingfunction against to the impact force from outside, resulting in makingit possible remarkably improve anti-chipping properties, to preventdevelopment of rust and corrosion on the steel material due to chipping,and to solve degradation of the topcoat coating film due to collisionwith rock salt, gravel and the like.

[0171] The water based chipping primer coating composition mainlycontain a water based vehicle and water, and further optionally containa viscosity-imparting agent, organic solvent, color pigment, extenderpigment, anti-corrosive pigment and the like.

[0172] The water based vehicle preferably may include a thermoplasticresin showing good adhesion properties to the electrodeposition coatingfilm and an intercoat coating film, and having a static glass transitiontemperature in the above-mentioned range, specifically the water basedbarrier coat as disclosed in Japanese Patent Publication No. 79699/94,(?)which is summarized as follows.

[0173] The water based vehicle may include the following ones:

[0174] {circle over (1)} modified polyolefin based resin:

[0175] For example, a mixture of 1 to 50 parts by weight, preferably 10to 20 parts by weight of a chlorinated polyolefin, for example,polypropylene having a degree of chlorination in the range of about 1(one) to 60% by weight, with 100 parts by weight of a propylene-ethylenecopolymer (preferably a molar ratio in the range of 40 to 80:60 to 20);a graft polymer obtained by a graft polymerization of 1 to 50 parts byweight, preferably 0.3 to 20 parts by weight of maleic acid or maleicanhydride to 100 parts by weight of the propylene-ethylene copolymer,and the like. These copolymers, chlorinated polyolefin and graft polymergenerally has a number average molecular weight in the range of about5,000 to about 300,000;

[0176] {circle over (2)} styrene-butadiene copolymer:

[0177] a copolymer having a styrene content of 1 to 50% by weight,preferably 10 to 40% by weight and prepared by optionally adding afunctional monomer such as acrylic acid, methacrylic acid and the liketo styrene and butadiene, followed by subjecting to an emulsionpolymerization in water in the presence of a polymerization catalyst,molecular weight controlling agent, surface active agent and the like.The polymerization temperature is in the range of 100° C. or lower. Thecopolymer preferably has a number average molecular weight in the rangeof about 10,000 to about 1,000,000;

[0178] {circle over (3)} butadiene resin:

[0179] a water-dispersed composition obtained by polymerization in theabsence of styrene, in the above {circle over (2)};

[0180] {circle over (4)} acrylonitrile-butadiene copolymer:

[0181] a copolymer having an acrylonitrile content of 1 to 50% byweight, preferably 10 to 40% by weight and obtained by optionally addinga functional monomer such as acrylic acid, methacrylic acid and the liketo acrylonitrile and butadiene, followed by subjecting to an emulsionpolymerization in water in the presence of a polymerization catalyst,molecular weight controlling agent, surface active agent and the like.The polymerization temperature is preferably in the range of 100° C. orlower. The copolymer has a number average molecular weight in the rangeof about 10,000 to about 1,000,000;

[0182] {circle over (5)} polybutene:

[0183] a polybutene obtained by subjecting a mixture of isobutylene as amain component and normal butylene as an optional component to a lowtemperature polymerization to obtain a polybutene, followed by heatingthe polybutene at 50 to 70° C. in the presence of an emulsifying agent,and adding water while sufficiently stirring. The resulting resinpreferably has a number average molecular weight in the range of about1,000 to about 500,000;

[0184] {circle over (6)} acrylic resin:

[0185] an acrylic resin prepared by subjecting a vinyl monomer componentobtained by mixing acrylate and/or methacrylate as a main component,optionally a functional monomer such as acrylic acid, methacrylic acid,hydroxyethyl acrylate, hydroxypropyl methacrylate and the like, and/orother polymerizable unsaturated monomer to an emulsion polymerization toform a water dispersion; or to a solution polymerization followed byforming an aqueous solution or a water dispersion. The acrylic resinpreferably has a number average molecular weight in the range of about5,000 to 1,000,000;

[0186] {circle over (7)} a natural rubber latex, methylmethacrylate-butadiene copolymer emulsion, polychloroprene emulsion,polyvinylydone emulsion and the like.

[0187] The coating film formed by the water based chipping primercoating composition preferably has a static glass transition temperature(Tg) in the range of 0 to −75° C., preferably −30 to −60° C., morepreferably −40 to −55° C. When the Tg is higher than 0° C., a finallyformed coating film show poor properties in anti-chipping properties,corrosion resistance, physical performances and the like. On the otherhand, when lower than −75° C., a finally formed coating film shows poorproperties in water resistance, adhesion properties and the like.

[0188] The chipping primer coating composition may also contain anextender pigment, color pigment, anti-corrosion pigment and the like. Amixing amount of these pigments preferably is in the range of 1 to 150parts by weight per 100 parts by weight (solid content) of the waterbased vehicle.

[0189] The water based chipping primer coating composition may be coatedby an air spray coating, airless spray coating, electrostatic coatingand the like so as to be a dry film thickness in the range of 1 to 20μm, preferably 5 to 10 μm.

[0190] The predrying of the water based chipping primer coating film maybe carried out to such an extent that coating film drawbacks such asbubbling, sagging, pinholes and the like may not develop duringheat-curing thereof along with an electrodeposition coating film and anintercoat coating film, specifically by drying at a surface temperatureof a coating substrate in the range of 10 to 80° C. for 1 to 60 minutes,preferably 2 to 30 minutes.

[0191] The water based chipping primer coating composition may beheat-cured at a surface temperature of coating substrate of 80 to 200°C., preferably 100 to 180° C. for 10 to 180 minutes, preferably 20 to 50minutes.

[0192] An intercoat coating composition comprising the heat-curablewater based coating composition or the heat-curable powder coatingcomposition is coated onto the water based chipping primer coating filmfor the purpose of improving smoothness, definition properties,interlayer adhesion properties-and the like.

[0193] The heat-curable topcoat coating composition is coated onto theintercoat coating film formed by coating the intercoat coatingcomposition.

[0194] In the third embodiment of the first invention, the water basedchipping primer coating composition is coated onto the electrodepositioncoating film for the purpose of improving smoothness, definitionproperties, interlayer adhesion properties, anti-chipping properties andthe like.

[0195] The topcoat coating composition is coated onto the water basedchipping primer coating film formed by coating the water based chippingprimer coating composition for the purpose of improving smoothness,definition properties, interlayer adhesion properties and the like.

[0196] In the first embodiment of the second invention, a method whichcomprises coating the heat-curable electrodeposition coating compositiononto the surface of the oxidized aluminum material to form anelectrodeposition coating film, followed by heat-curing is asabove-described.

[0197] In the second embodiment of the second invention, formation ofthe water based intercoat coating film or intercoat powder coating filmonto the surface of the oxidized aluminum material, followed byheat-curing, and formation of the topcoat coating film, followed byheat-curing may be carried out by the methods described in the firstembodiment of the first invention.

[0198] In the third invention, the surface treatment subjected to thealuminum material is the same as that described in the first and secondinvention.

[0199] In the third invention, the oxidizing treatment of the aluminummaterial is the same as that in the second invention.

[0200] The coating method of the third invention, in the case the solemetal base material such as aluminum material, aluminum-coated steelmaterial and the like is used, may include the following methods, forexample,

[0201] (1) a method which comprises subjecting the metal base materialto a press molding into a predetermined part material such as an enginehood, fender panel and the like, followed by assembling to theautomobile body, optionally and respectively carrying out the surfacetreatment, electrodeposition coating, water based chipping primercoating and intercoat coating, and applying the film facing material;

[0202] (2) a method which comprises subjecting the metal base materialto a press molding into a predetermined part material such as an enginehood, fender panel and the like, optionally and respectively carryingout the surface treatment, electrodeposition coating, chipping primercoating and intercoat coating, and assembling to the automobile body,and applying the film facing material.

[0203] In the above assembling, respective coating compositions andcoating methods (predrying and heat-curing) may include ones known inthe art, for example, may include 4 coats 1 bake (a coating method offormation of a multi-layer coating film comprising wet or predried 3coats of electrodeposition coating, chipping primer coating, andintercoat coating followed by simultaneous heat-curing, hereinafterreferred to the same meaning), 4 coats 2 bakes, 4 coats 3 bakes, 4 coats4 bakes, 3 coats one bake (3 coats of electrodeposition coating,chipping primer coating, intercoat coating), 3 coats 2 bakes, 3 coats 3bakes, 2 coats one bake (2 coats of electrodeposition coating andchipping primer coating, 2 coats of electrodeposition coating andintercoat coating or 2 coats of chipping primer coating and intercoatcoating), one coat one bake (one coat of electrodeposition coating,chipping primer coating or intercoat coating), and the like.

[0204] The coating method of the third invention, in the case where analuminum material and steel material-combined metal material is used asthe base material of the automobile body, may include, for example, amethod which comprises subjecting the steel material to a press moldinginto a predetermined part material such as an engine hood, fender paneland the like, followed by subjecting to a surface treatment, assemblingthe surface-treated steel part material to the automobile body,respectively subjecting to electrodeposition coating, water basedchipping primer coating, intercoat coating and topcoat coating to obtaina topcoat-coated steel part material-assembled automobile body;separately subjecting the aluminum base material to a press molding intoa predetermined part material different from the above part material,for example, a bonnet and the like, optionally and respectively followedby subjecting to a surface treatment, electrodeposition coating,chipping primer coating, and intercoat coating, and by applying the filmfacing material to obtain a film facing material-applied aluminum partmaterial, and assembling the film facing material-applied aluminum partmaterial to the topcoat-coated steel material-assembled automobile body.The application method is not limited to the above method.

[0205] The film facing material may include ones known in the art,specifically, for example, an application film prepared by combining acementing material layer (a), a substrate base material layer (b), acolored film (c) and a clear layer (d).

[0206] The cementing material layer (a) is an adhesive layer to applythe substrate base material layer (b) onto a coating substrate such asaluminum material, optionally the electrodeposition coating film,chipping primer coating film, intercoat coating film and the like. Thecementing material used in the cementing material layer (a) may includeones known in the art, for example, a beat-curable, cold-curable,actinic ray-curable or thermoplastic adhesive and pressure-sensitiveadhesive and the like, which contains a curing agent and at least oneresin selected from bisphenol type epoxy resin, resol type epoxy resin,acrylic resin, aminoplast resin, polyester resin, urethane resin,polysiloxane resin, (iso)butylene resin, vinyl acetate resin, vinylchloride resin, vinyl chloride-vinyl acetate copolymer, syntheticrubber, natural rubber and the like. The cementing may be transparent orcolored.

[0207] These cementing material may include a pressure-sensitiveadhesive, heat-sensitive adhesive, curable type adhesive and the like.

[0208] The cementing material layer (a) has a film thickness in therange of 1 to 100 μm, preferably 5 to 80 μm.

[0209] The substrate base material layer (b) is a base material layer tomake the application operation easy, and examples of the substrate basematerial may include thermoplastic resins such as polyethylene,polypropylene, polyisobutylene, polybutadiene, polystyrene,polychloroprene, polyvinyl chloride, polyvinyl acetate, nylon, acrylicresin, polycarbonate, cellulose, polyethylene terephthalate, polyacetal,AS resin, ABS resin and the like, aluminum foil, and the like. Thesubstrate base material layer may be transparent or colored.

[0210] The substrate base material layer (b) has a film thickness in therange of 10 to 200 μm, preferably 20 to 150 μm.

[0211] The colored film (c) may include, for example, a coating filmformed by a coating composition prepared by adding a color pigment tothe curable resin known in the art, for example, a base coatingcomposition used in the field of the automobile coating composition, andformed by ink and the like.

[0212] The curable resin may include, for example, amino-curing resin,(blocked) polyisocyanate-curing resin, acid epoxy-curing resin,hydrolyzable silane-curing resin, hydroxyl group-epoxy group-curingresin, hydrazine-curing resin, oxydation polymerization-curing resin,photo (heat) radical polymerization type resin, photo (heat) cationicpolymerization type resin, and curable resins in combination with atleast two of the above resins.

[0213] The color pigment may include ones known in the art, for example,white pigment such as titanium oxide, zinc oxide, basic lead carbonate,basic sulfate white lead, lead sulfate, lithopone, zinc sulfide,antimonum white, antimony white and the like; black pigment such ascarbon black, acetylene black, lamp black, bone black, graphite, ironblack, aniline black and the like; yellow pigment such as naphtholyellow S, hansa yellow, pigment yellow L, benzidine yellow, permanentyellow and the like; orange pigment such as chrome orange, chromevermilion, permanent orange and the like; brown pigment such as ironoxide, amber and the like; red pigment such as red iron oxide, red lead,permanent red, quinacridone and the like; violet pigment such as cobaltblue, fast violet, methylviolet lake and the like; blue pigment such asultramarine, prussian blue, cobalt blue, phthalocyanine blue, indigo andthe like; green pigment such as chrome green, pigment green B,phthalocyanine green, and the like; mica, colored mica, flake aluminumpowder and the like.

[0214] Kinds of the coating composition by use of the above curableresin may include powder coating composition, non-solvent type coatingcomposition including a non-solvent type coating composition prepared bydissolving or dispersing a crosslinkable or non-crosslinkable resin intoa radically polymerizable monomer, a water based coating compositionprepared by dissolving or dispersing a curable resin into water, anorganic solvent based coating composition prepared by dissolving ordispersing a curable resin into an organic solvent, including anon-water dispersion type coating composition, and the like.

[0215] A mixing ratio of the curable resin to the color pigment mayarbitrarily be determined depending on uses and finished appearance, butusually is such that the color pigment is in the range of 0.01 to 200parts by weight, preferably 0.1 to 100 parts by weight per 100 parts byweight (as solid content) of the curable resin.

[0216] The colored coating film layer has a film thickness in the rangeof 1 to 100 μm, particularly 2 to 80 μm. The colored coating film layermay be a monolayer or a multi-color multi-layer film formed bylaminating at least two colored layers. The coating film may optionallyhas a pattern such as letters, pictures, figures, markings and the like,and may also be colored to such an extent that the substrate underneathis visible.

[0217] The colored film layer may be formed by a coating method suitablefor a kind of the curable coating composition, for example, rollercoating, brushing, electrostatic coating, powder coating,electrodeposition coating, air spray coating, airless spray coating,screen printing, gravure printing and the like.

[0218] The colored film layer may be cured by a suitable curing methodsuch as irradiation, heating and the like and under suitable curingconditions depending on the kind of the resin composition. For example,curing in the case of the heat-curable resin may be carried out byheating at a temperature in the range of about 100° C. to about 170° C.for about 10 minutes to about 40 minutes.

[0219] The colored film layer (c) may have a film thickness in the rangeof 1 to 100 μm, preferably 20 to 80 μm.

[0220] A clear coating composition may be coated onto the surface of thecolored film layer (c) to form a clear layer (d), which may be coloredto such an extent that a substrate underneath may be visible. The clearcoating composition may include a coating composition prepared by addinga color pigment to the curable resin known in the art, for example, aclear coating composition conventionally used in the field of theautomobile coating composition, and a coating composition formed fromink, and the like.

[0221] The unable resin may include, for example, amino-curing resin,(blocked) polyisocyanate-curing resin, acid epoxy-curing resin,hydrolyzable silane-curing resin, hydroxyl group-epoxy group-curingresin, hydrazine-curing resin, oxydation polymerization-curing resin,photo (heat) radical polymerization type resin, photo (heat) cationicpolymerization type resin, and curable resins in combination with atleast two of the above resins. The clear coating composition may becured by the same coating method and curing conditions as those abovedescribed.

[0222] The clear layer (d) has a film thickness in the range of 1 to 100μm, preferably 2 to 80 μm.

[0223] The use of a colored substrate base material prepared by adding acolor pigment to the substrate base material layer (b) per se makes itpossible to exclude the colored film (c).

[0224] The film facing material may be applied onto the surface of thesubstrate by pressing the surface of the cementing material layer (a)onto the surface of the substrate, followed by pressurizing from overthe clear layer (d). This application may be carried out directly byhand, by hand using a squeegees or by use of an automobile applicationmachine.

[0225] The transfer film known in the art may also be used as the filmfacing material of the present invention.

[0226] The transfer film may include, for example, a transfer filmprepared by laminating an application film layer obtained by laminatinga pressure-sensitive cementing material onto the plastic film such aspolyethylene terephthalate sheet having a film thickness of 20 to 10 μm,preferably 30 to 80 μm and removed after transferring, the clear layer(d), colored film (c), the pressure-sensitive cementing material layer(a) and a release layer removed after transferring.

[0227] The transfer film may be applied by removing the release layerfrom the transfer film, followed by pressing the surface of the exposedpressure-sensitive cementing material layer (a) onto the surface of thesubstrate, and by pressurizing from over the application film. Afterapplication, the application film is separated from the surface of theclear layer.

[0228] In the case where a colored aluminum material obtained by naturalcolor development on electrolytic coloring is used as the aluminummaterial and the film facing material is transparent, the coloredaluminum material is visible through the film facing material, resultingin making it possible to obtain a coating film showing excellentproperties in finished appearance as impossible by coating theconventional automobile coating composition. In addition, the use of acolor clear layer colored to such an extent that the substrateunderneath is visible by transmission results in that an incident lightfrom the surface of the color clear coating film transmits through thecolor clear coating film, that a light transmitted through the colorclear coating film is identified by a person as a reflected light, andthat a combination of a color due to the colored aluminum material witha transmitted light due to the color clear coating film makes itpossible to develop a particular color. The first embodiment of thefirst invention makes it possible to form a multi-layer coating filmcomprising a tri-layer structure suitable for coating of the automobilebody simply, economically, in a power-saving way, safely, stably andcontinuously, and to form a multi-layer coating film showing goodproperties in finish appearance and coating film performances. The useof the aluminum material having a degree of surface roughness of 0.2 μmor less makes it possible to further improve the finish appearance ofthe multi-layer coating film comprising tri-layer structure.

[0229] The second embodiment of the first invention makes it possible toform a multi-layer coating film comprising four-layer structure suitablefor coating the automobile body simply, economically, in a power-savingway, safely, stably and continuously, and to form a multi-layer coatingfilm showing good properties in finish appearance and coating filmperformances.

[0230] In the present invention, application of a strong impact forcedue to collision of rock salt, gravel and the like onto the surface of amulti-layer coating film comprising the water based chipping primercoating film having the above physical properties, the intercoat coatingfilm and topcoat coating film may result that all or almost all of theimpact energy may be absorbed into the water based chipping primercoating film without reaching the electrodeposition coating filmunderneath, and that both the intercoat coating film and topcoat coatingfilm are subjected to almost no physical damage. That is, the waterbased chipping primer coating film shows a shock-absorbing functionagainst to the impact force from outside, resulting in making itpossible remarkably improve anti-chipping properties, to preventdevelopment of rust and corrosion on the steel material due to chipping,and to solve degradation of the topcoat coating film due to collisionwith rock salt, gravel and the like.

[0231] The use of the aluminum material having a degree of surfaceroughness of 0.2 μm or less makes it possible to further improve thefinish appearance of the multi-layer coating film comprising tri-layerstructure.

[0232] The third embodiment of the first invention makes it possible toform a multi-layer coating film comprising a four-layer structuresuitable for coating of the automobile body simply, economically, in apower-saving way, safely, stably and continuously, and to form amulti-layer coating film showing good properties in finish appearanceand coating film performances.

[0233] application of a strong impact force due to collision of rocksalt, gravel and the like onto the surface of a multi-layer coating filmcomprising the water based chipping primer coating film having the abovephysical properties and topcoat coating film may result that all oralmost all of the impact energy may be absorbed into the water basedchipping primer coating film without reaching the electrodepositioncoating film underneath, and that both the intercoat coating film andtopcoat coating film are subjected to almost no physical damage, thatis, the water based chipping primer coating film shows a shock-absorbingfunction against to the impact force from outside, resulting in makingit possible remarkably improve anti-chipping properties, to preventdevelopment of rust and corrosion on the steel material due to chipping,and to solve degradation of the topcoat coating film due to collisionwith rock salt, gravel and the like.

[0234] The use of the aluminum material having a degree of surfaceroughness of 0.2 μm or less makes it possible to further improve thefinish appearance of the multi-layer coating film comprising tri-layerstructure.

[0235] The first embodiment of the second invention makes it possible toform an electrodeposition coating film suitable for coating theautomobile body simply, economically, in a power-saving way, safely,stably and continuously, and to form an electrodeposition coating filmshowing good properties in finished appearance and coating filmperformances.

[0236] The use of the oxidized aluminum material having a degree ofsurface roughness of 0.2 μm or less makes it possible to further improvethe finish appearance of the electrodeposition coating film.

[0237] The second embodiment of the second invention makes it possibleto form an intercoat coating film and a topcoat coating film suitablefor coating the automobile body simply, economically, in a power-savingway, safely, stably and continuously, and to form an intercoat coatingfilm and a topcoat coating film showing good properties in finishedappearance and coating film performances. The use of the oxidizedaluminum material having a degree of surface roughness of 0.2 μm or lessmakes it possible to further improve the finish appearance of theintercoat coating film and topcoat coating film.

[0238] The film facing material of the third invention provides thefollowing effects {circle over (1)} to {circle over (7)}:

[0239] {circle over (1)} A coating film showing good finish appearanceand having a pearl gloss can be obtained;

[0240] {circle over (2)} The film facing material having the substratebase material layer is such that on collision of external objects suchas rock salt, gravel and the like to the surface of the film, thesubstrate base material layer absorbs an impact energy from the surface,resulting in making it possible to obtain a coating film showing goodproperties in durability without any-coating film drawbacks such ascracks, peeling off and the like in spite of hard surface, and making itpossible to maintain the film performances for a long period of time;

[0241] {circle over (3)} The film surface formed from a cured resinshows a high hardness, good properties in chemical resistance, pollutionresistance, sanding resistance;

[0242] {circle over (4)} Application of the film facing material iseasy, and provides good finish appearance without producing drawbackssuch as wrinkles and the like;

[0243] {circle over (5)} There is no need of coating the melamine-curingresin coating composition, isocyanate-curing resin coating composition,acid-curing resin coating composition and the like directly onto thebase material, a suitable method can be selected beforehand depending oncoating purpose, for example, coating methods, coating filmperformances, finish appearance and the like. Further effects can beprovided, for example, coating film drawbacks due to coating iscontrolled, coating composition is not consumed in excess amount,working environments, health and safety control are improved, and usedcoating can be recovered without environmental pollution;

[0244] {circle over (6)} The use of the aluminum material having adegree of surface roughness of 0.2 μm or less can improve finishappearance;

[0245] {circle over (7)} The use of a colored aluminum material coloredby natural color development and electrolytic coloring makes it possibleto provide an automobile body showing metallic feeling and fine finishappearance as impossible in the case of the conventional automobilecoating composition.

EXAMPLE

[0246] The present invention is explained more in detail by thefollowing Examples and Comparative Examples, in which “part” and “%”represent “part by weight” and “% by weight” respectively. The presentinvention is not limited to the Examples.

Example 1

[0247] A 0.8 mm thick aluminum plate material (JIS A6061) was subjectedto a degreasing washing, followed by subjecting to a surface treatmentwith a zinc phosphate based treating agent, coating a cationicelectrodeposition coating composition Elecron GT-10 (blockedpolyisocyanate-curing epoxy resin electrodeposition coating composition,trade name, marketed by Kansai Paint Co., Ltd.), heat-curing at 170° C.for 20 minutes so as to obtain an electrodeposition coating plate havinga dry coating film thickness of about 20 μm, spray coating the followingheat-curable water based intercoat coating composition so as to be afilm thickness of 30 μm heat-curing at 140° C. for 20 minutes, spraycoating a heat-curable topcoat coating composition (Neoamilac #6000white, trade name, marketed by Kansai Paint Co., Ltd. organic solventbased) so as to be a dry film thickness of about 80 μm, and heat-curingat 140° C. for 20 minutes to obtain respective test coating plate.

Examples 2-26

[0248] Respective test coating plates of Examples 2-26 were prepared bythe methods as described in Tables 1 and 2.

Examples 27-38

[0249] A 0.8 mm thick aluminum plate material (JIS A6061) was subjectedto a degreasing washing, followed by subjecting to a surface treatmentwith a zinc phosphate treating agent to obtain a surface-treatedaluminum material, separately a zinc-iron alloy molten zinc-plated steelplate was subjected to a surface treatment with a zinc phosphatetreating agent, coating a following cationic electrodeposition coatingcomposition so as to be a film thickness of 20 μm, washing with water,heat-curing at 170° C. for 20 minutes to obtain an electrodepositioncoating-treated steel plate, welding the surface-treated aluminummaterial and the coating-treated steel plate so that both coatingsurfaces are in the same side, subjecting both aluminum plate materialand steel plate material to coating under the coating conditions asdescribed in Tables 1 and 2.

[0250] In Tables 1 and 2, the anodized treatment was carried out asfollows.

[0251] A 0.8 mm thick aluminum plate material (JIS A6061) was subjectedto a pretreatment, followed by subjecting to an anodizing treatment in a150 g/· aqueous sulfuric acid solution at 20° C. and a current densityof −120 A/m² for 30 minutes to form an anodized film to be used. TABLE 1(1) Examples Conditions 1 2 3 4 5 6 7 8 9 10 11 12 base materialaluminum aluminum degrees of surface 0.2 or less material alloyroughness (μm) surface treatment zinc phosphate based treating agentanodized treatment electrodeposition coating-treated steel plateElectrodeposition coating cationic film thickness 20 μm ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯◯ ◯ ◯ ◯ electrodesposition predrying 60° C. - 1 minute ◯ ◯ ◯ ◯heat-curing 170° C. - 20 minutes ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ anionic film thickness20 μm electrodesposition predrying 60° C. - 1 minute heat-curing 170°C. - 20 minutes Intercoat coating water based film thickness 30 μm ◯ ◯ ◯◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ intercoat coating predrying 60° C. - 1 minute ◯ ◯ ◯ ◯composition heat-curing 140° C. - 20 minutes ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ powder filmthickness 40 μm intercoat coating predrying 90° C. - 5 minutescomposition heat-curing 170° C. - 20 minutes Topcoat coatingheat-curable kind organic solvent based ◯ ◯ ◯ topcoat coating waterbased ◯ ◯ ◯ composition powder ◯ ◯ ◯ (colored) powder water ◯ ◯ ◯dispersion based film thickness 20 μm ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯heat-curing 140° C. ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ 170° C. 20 minutes ◯ ◯ ◯ ◯ ◯◯ ◯ ◯ ◯ ◯ ◯ ◯ heat-curable base organic solvent topcoat coating basedcomposition water based (base/clear) film thickness 30 μm predrying 90°C. - 5 minutes heat-curing 140° C. 170° C. 20 minutes clear organicsolvent based water based powder powder water dispersion based filmthickness 40 μm heat-curing 140° C. 170° C. 20 minutes ultravioletlight- irradiation dose of 150 curable clear mJ/cm² by use of 3 kWtopcoat coating ultrahigh pressure composition mercury lamp Test resultscoating film smoothness ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ appearance and gloss 9189 92 90 88 91 87 86 87 85 84 86 coating film definition properties 8080 81 89 79 82 86 85 86 83 81 82 performances adhesion properties ◯ ◯ ◯◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ (aluminum corrosion resistance ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯material) salt water resistance ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ anti-chippingproperties ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯

[0252] TABLE 1 (2) Examples Condition 13 14 15 16 17 18 19 20 21 22 23base material aluminum aluminum degree of surface 0.2 or less materialalloy roughness (μm) surface treatment zinc phosphate based treatingagent anodized treatment electrodeposition coating-treated steel plateElectrodeposition coating cationic film thickness 20 μm ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯◯ ◯ ◯ electrodeposition predrying 60° C. - 1 minute ◯ ◯ heat-curing 170°C. - 20 minutes ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ anionic film thickness 20 μmelectrodeposition predrying 60° C. - 1 minute heat-curing 170° C. - 20minutes Intercoat coating water based film thickness 30 μm ◯ ◯ ◯ ◯ ◯ ◯ ◯◯ ◯ intercoat predrying 60° C. - 1 minute ◯ ◯ coating heat-curing 140°C. - 20 minutes ◯ ◯ ◯ ◯ ◯ ◯ ◯ composition powder film thickness 40 μm ◯◯ intercoat predrying 90° C. - 5 minutes coating heat-curing 170° C. -20 minutes ◯ ◯ Topcoat coating heat-curable kind organic solvent based ◯◯ topcoat coating water based composition powder (colored) powder waterdispersion based film thickness 40 μm ◯ ◯ heat-curing 140° C. ◯ ◯ 170°C. 20 minutes ◯ ◯ heat-curable base organic solvent ◯ topcoat coatingbased composition water based ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ (base/clear)film-thickness 20 μm ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ predrying 90° C. - 5 minutes ◯ ◯◯ ◯ ◯ ◯ ◯ heat-curing 140°C. ◯ 170° C. ◯ 30 minutes ◯ ◯ ◯ ◯ ◯ clearorganic solvent ◯ ◯ based water based ◯ ◯ ◯ ◯ powder ◯ powder water ◯dispersion based film thickness 40 μm ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ heat-curing 140°C. 170° C. ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ 20 minutes ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ultraviolet light-irradiation dose of 150 ◯ curable clear mJ/cm² by use of 3 kW topcoatcoating ultrahigh pressure composition mercury lamp Test results coatingfilm smoothness ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ appearance and gloss 90 91 89 8381 92 91 92 93 83 83 coating film definition properties 80 81 81 79 7880 80 81 81 79 78 performance adhesion properties ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯(aluminum corrosion resistance ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ material) saltwater resistance ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ anti-chipping properties ◯ ◯ ◯ ◯◯ ◯ ◯ ◯ ◯ ◯ ◯

[0253] TABLE 2 (1) Examples Conditions 24 25 26 27 28 29 30 31 32 33 34base material aluminum aluminum degree of surface 0.3 or more 0.2 orless material alloy roughness (μm) surface treatment zinc phosphatebased treating agent anodized treatment ◯ ◯ electrodepositioncoating-travel ◯ steel plate Electrodeposition coating cationic filmthickness 20 μm ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ electrodeposition predrying 60° C. - 1minute ◯ ◯ ◯ heat-curing 170° C. - 20 minutes ◯ ◯ ◯ ◯ ◯ ◯ anionic filmthickness 20 μm ◯ ◯ electrodesposition predrying 60° C. - 1 minuteheat-curing 170° C. - 20 minutes ◯ ◯ Intercoat coating water based filmthickness 30 μm ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ intercoat coating predrying 60° C. - 1minute ◯ ◯ ◯ composition heat-curing 140° C. - 20 minutes ◯ ◯ ◯ ◯ ◯ ◯ ◯◯ powder intercoat film thickness 40 μm coating predrying 90° C. - 5minutes composition heat-curing 170° C. - 20 minutes Topcoat coatingheat-curable kind organic solvent based ◯ ◯ ◯ ◯ topcoat coating waterbased ◯ ◯ ◯ ◯ composition powder ◯ ◯ (colored) powder water dispersionbased film thickness 40 μm ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ heat-curing 140° C. ◯ ◯ ◯◯ ◯ ◯ ◯ ◯ ◯ 170° C. ◯ 20 minutes ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ heat-curable baseorganic solvent based topcoat coating water based ◯ composition filmthickness 20 μm ◯ (base/clear) predrying 90° C. - 5 minutes ◯heat-curing 140° C. 170° C. 20 minutes clear organic solvent based waterbased ◯ powder powder water dispersion based film thickness 40 μm ◯heat-curing 140° C. 170° C. ◯ 20 minutes ◯ ultraviolet irradiation doseof 150 mJ/cm² light-curable clear by use of 3 kW ultrahigh topcoatcoating pressure mercury lamp composition Test results coating filmsmoothness ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ appearance and gloss 86 85 86 91 89 9290 88 91 87 86 coating film definition properties 83 81 88 80 80 81 8979 82 86 85 performances adhesion properties ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯(aluminum corrosion resistance ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ material salt waterresistance ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ anti-chipping properties ◯ ◯ ◯ ◯ ◯ ◯ ◯◯ ◯ ◯ ◯ coating film smoothness ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ appearance and gloss 8987 90 88 86 88 85 82 coating film definition properties 78 78 79 85 7780 85 81 performances adhesion properties ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯(surface-treated corrosion resistance ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ steel plate saltwater resistance ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ anti-chipping properties ◯ ◯ ◯ ◯ ◯ ◯ ◯◯

[0254] TABLE 2 (2) Examples Conditions 35 36 37 38 base materialaluminum aluminum degree of surface 0.2 or more material alloy roughness(μm) surface treatment zinc phosphate based treating agent anodizedtreatment electrodeposition coating-treated steel plateElectrodeposition coating cationic film thickness 20 μm ◯ ◯ ◯ ◯electrodeposition predrying 60° C. - 1 minute ◯ heat-curing 170° C. - 20minutes ◯ ◯ ◯ anionic film thickness 20 μm electrodeposition predrying60° C. - 1 minute heat-curing 170° C. - 20 minutes Intercoat coatingwater based film thickness 30 μm ◯ ◯ ◯ ◯ intercoat predrying 60° C. - 1minute ◯ ◯ coating composition heat-curing 140° C. - 20 minutes ◯ ◯powder film thickness 40 μm intercoat predrying 90° C. - 5 minutescoating heat-curing 170° C. - 20 minutes composition Topcoat coatingheat-curable kind organic solvent based topcoat coating water basedcomposition powder ◯ (colored) powder water dispersion ◯ ◯ ◯ based filmthickness 20 μm ◯ ◯ ◯ ◯ heat-curing 140° C. ◯ ◯ ◯ ◯ 170° C. 20 minutes ◯◯ ◯ ◯ heat-curable base organic solvent based topcoat coating waterbased composition film thickness 20 μm (base/clear) predrying 90° C. - 5minutes heat-curing 140° C. 170° C. 20 minutes clear organic solventbased water based powder powder water dispersion based film thickness 40μm heat-curing 140° C. 170° C. 20 minutes ultraviolet light- irradiationdose of 150 mJ/cm² curable clear by use of 3 kW ultrahigh topcoatcoating pressure mercury lamp composition Test results coating filmsmoothness ◯ ◯ ◯ ◯ appearance and gloss 87 85 84 86 coating filmdefinition properties 86 83 81 82 performances adhesion properties ◯ ◯ ◯◯ (aluminum corrosion resistance ◯ ◯ ◯ ◯ material) salt water resistance◯ ◯ ◯ ◯ anti-chipping properties ◯ ◯ ◯ ◯ coating film smoothness ◯ ◯ ◯ ◯appearance and gloss 84 81 82 85 coating film definition properties 8480 78 80 performances adhesion properties ◯ ◯ ◯ ◯ (surface-treatedcorrosion resistance ◯ ◯ ◯ ◯ steel plate salt water resistance ◯ ◯ ◯ ◯anti-chipping properties ◯ ◯ ◯ ◯

Comparative Examples 1-2

[0255] Respective coating plates of Comparative Examples 1-2 wereprepared in the same manner as described in Table 1. TABLE 3 ComparativeExamples Conditions 1 2 base material aluminum aluminum degree ofsurface 0.5 or more material alloy roughness (μm) surface treatmentanodized treatment electrodeposition coating-treated steel plate ◯Electrodeposition coating cationic film thickness 20 μm ◯ ◯electrodeposition predrying 60° C. - 1 minute heat-curing 170° C. - 20minutes ◯ ◯ anionic film thickness 20 μm electrodeposition predrying 60°C. - 1 minute heat-curing 170° C. - 20 minutes Topcoat coatingheat-curable kind organic solvent based ◯ ◯ topcoat coating powdercomposition powder water dispersion based (colored) film thickness 40 μm◯ ◯ heat-curing 140° C. ◯ ◯ 170° C. 20 minutes ◯ ◯ Test results coatingfilm smoothness Δ Δ appearance and gloss 70 65 coating film definitionproperties 65 60 performances adhesion properties ◯ ◯ (aluminumcorrosion resistance ◯ ◯ material) salt water resistance ◯ ◯anti-chipping properties Δ Δ

[0256] Electrodeposition coating in Tables 1, 2 and 3 represents anelectrodeposition coating method and conditions as applied to thealuminum material.

[0257] In Tables 1, 2 and 3, base material, coating composition and testmethod as described as follows.

[0258] Surface-Treated Steel Plate:

[0259] A zinc iron alloy or zinc-plated steel plate was subjected to asurface treatment with a zinc phosphate treating agent.

[0260] Cationic Electrodeposition Coating Composition:

[0261] Elecron GT-10 (trade name, marketed by Kansai Paint Co., Ltd.,blocked polyisocyanate-curing epoxypolyamino based resin,electrodeposition coating composition).

[0262] Anionic Electrodeposition Coating Composition:

[0263] Elecron AG210 (trade name, marketed by Kansai Paint Co., Ltd.,-curing acrylic resin electrodeposition

coating composition).

[0264] Water Based Intercoat Coating Composition:

[0265] A mixture of 1000 parts (as solid content, and

polye

resin (a polyester resin prepared by introducing into a reactor amixture of 756 parts of neopentyl glyco

109 parts of trimethylolpropane, 370 parts of hexahydrophthalic acid,292 parts of adipic acid and

parts of isophthalic acid, followed by reacting at 220° C. for 6 hours,adding 45 parts of trimellitic anhydride

reacting at 170° C. for 30 minutes to obtain a poly

resin heaving a number average molecular weight of about 8,000, an acidvalue of 20 mg KOH/g, and a hydroxy value of 95 mg KOH/g), 40 parts ofdimethylaminoethanol, 410 parts of a curing agent prepared by blockingtrimer adduct of hexamethylene diisocyanate methylethylketoxime, 1400parts of titanium white pigment (Tayca JR806, trade name, marketed byTayca Corporation) and 2 parts of carbon black (Mitsubishi Carbon BlackM-100 (trade name, marketed by Mitsubishi Chemical Corporation) wasmixed and dispersed into 1800 parts of deionized water to obtain awater-based intercoat coating composition.

[0266] Powder Intercoat Coating Composition:

[0267] Everclad

4000 White (trade name, marketed by Kansai Paint Co., Ltd., heat-curablepoly

coating composition).

[0268] Heat-Curable

[0269] Organic

marketed by Kansai Paint Co., Ltd.,

acrylic

[0270] Water Based

[0271] A mixture of

parts of titanium

and 2 parts of carbon black was added to a mixture of 140 parts of anacrylic resin neutralized solution (

) having a solid content of 50%, and 34 parts of

(trade name, marketed by Mitsui Cytec Ltd., 88% water-soluble melamineresin

solution), followed by dispersing and controlling a solid

content at 35% with deionized water to obtain a heat

-curable water based colored composition.

[0272] (Note 1): A Mixture of 30 parts of methyl methacrylate, 23 partsof ethyl acrylate, 30 parts of butyl acrylate, 12 parts of hydroxyethylmethacrylate and 5 parts of acrylic acid was subjected to obtain anacrylic resin solution (solid content 60%) having an acid value of 40, ahydroxy value of 52 and a number average molecular weight of about10000, followed by adding dimethylaminoethanol and neutralizing, anddiluting with isopropyl alcohol so as to a solid content of 50% toobtain an acrylic resin neutralized solution.

[0273] Powder Based:

[0274] Everclad 5000 White (trade name, marketed by Kansai Paint Co.,Ltd., heat-curable acrylic resin powder coating composition).

[0275] Powder Water Dispersion Cases:

[0276] A mixture prepared by adding 100 parts of a coating compositionsolution (A) to an aqueous polymer solution comprising 29 parts of 30%suspension-stabilizing agent water-soluble acrylic resin aqueoussolution (A) and 88 parts of ion exchange water was mixed by use of ahomogenizer at 14000 rpm to obtain a suspension, diluting with 45 partsof deionized water, introducing into a reactor equipped with a stirringapparatus, a temperature controller, reflux tube, and a vacuumapparatus, heating up to 55° C., controlling at 120 mmHg, carrying outdesolvation until a heating residue becomes 32%, filtering with a 200mesh silk cloth, removing agglomerates, adding 2.0 parts of apolymerizable urethane based thickening agent PUR-60 (trade name,marketed by Huls A. G.) to obtain a powder water dispersion basedcoating composition.

[0277] Aqueous Solution (A):

[0278] A reaction product of a mixture of 65 parts of n-butanol, 20parts of polyethylene oxide (45 mer), 10 parts of hydroxyethyl acrylate,15 parts of acrylic acid, 25 parts of methyl methacrylate, 20 parts ofn-butyl methacrylate and 10 parts of styrene was neutralized withdimethylethanolamine at 0.7 equivalent, adding deionized water anddiluting to be a resin content of 30% by weight.

[0279] Coating Composition (B):

[0280] A mixture of 100 parts of titanium white and 50 parts of blockedNCO curing agent B-1530 (trade name, marketed by Huls A. G.,ε-caprolactam IPDI isocyanurate) was added to a radical polymerizationreaction product resin solution of a mixture of 25 parts of hydroxyethylmethacrylate, 30 parts or styrene, 20 parts of butyl methacrylate, and25 parts of iso-butyl methacrylate to obtain a coating composition.

[0281] Heat-Curable Topcoat Coating Composition (For 2 Coats):

[0282] Base Coating Composition:

[0283] Organic Solvent Based:

[0284] An mixture of 75 parts of hydroxyl group-containing acrylic resin(number average molecular weight 15000, hydroxy value 50, acid value 4),25 parts (solid content) of methyl butyl mixed etherified melamine resin(U-Van: 20SE, trade name, marketed by Mitsui Toatsu Chemicals, Inc.) and25 parts of Alumipaste 891K (trade name, marketed by Toyo Aluminum K.K.)was mixed with a mixed solvent comprising ethyl acetate to toluene=50 to50 (weight ratio) for dispersing so that a solid content may be 40% oncoating.

[0285] Water Based:

[0286] A mixture of 100 parts of the 50% solid content acrylic resinneutralized solution (above Note 1), 100 parts of a 50% solid contentpolyester resin neutralized solution (Note 2), 500 parts of a 20% solidcontent acrylic emulsion (Note 3) and 38 parts of Cymel 370 (above tradename) was prepared, followed by adding 25 parts of Alumipaste 891K(trade name, marketed by Toyo Aluminum K.K.), and mixing to obtain aheat-curable water based metallic coating composition.

[0287] (Note 2) A mixture of 0.7 mole of neopentyl glycol, 0.3 mole oftrimethylolpropane, 0.4 mole of phthalic anhydride and 0.5 mole ofadipic acid was subjected to an esterification reaction, followed byadding 0.03 mole of trimellitic anhydride and reacting, adding butylcellosolve to obtain a polyester resin solution (solid content 70%)having an acid value of 40 and a number average molecular weight ofabout 6000, adding dimethyl aminoethanol and neutralizing, and dilutingwith isopropyl alcohol so as to a solid content of 50% to obtain apolyester resin neutralized solution.

[0288] (Note 3) A reactor was charged with 140 parts of deionized water,2.5 parts of Newcol 707SF (trade name, marketed by Nippon Newkazai Co.,Ltd., surface active agent) and one part of a monomer mixture A of 55parts of methyl methacrylate, 8 parts of styrene, 9 parts of butylacrylate, 5 parts of hydroxyethyl acrylate, 2 parts of 1,6-hexanedioldiacrylate and one part of methacrylic acid, followed by mixing withagitation under nitrogen gas atmosphere, heating at 60° C., adding 3parts of 3% ammonium persulfate aqueous solution, heating up to 80° C.,adding a monomer emulsion comprising 79 parts of the monomer mixtureA_(r) 2.5 parts of Newcol 707Sf (trade name as above), 4 parts of 3%ammonium persulfate aqueous solution and 2 parts of deionized water over4 hours, aging for one hour, dropping at 80° C. 20.5 parts of a monomermixture B of 5 parts of methyl methacrylate, 7 parts of butyl acrylate,5 parts of 2-ethyl hexyl acrylate, 3 parts of methacrylic acid and 0.5part of Newcol 707SF (trade name as above), and 4 parts of 3% ammoniumpersulfate aqueous solution simultaneously over 1.5 hours, aging for onehour; diluting with 30 parts of deionized water, adding deionized waterto the resulting filtrate, controlling pH at 7.5 withdimethylaminoethanol to obtain a 20% solid content acrylic emulsion.

[0289] Clear Coating Composition:

[0290] Organic Solvent Based:

[0291] A mixture of 57 parts of acrylic resin solution (Note 4), 50parts of acrylic resin non-water dispersion (Note 5), 30 parts of Cymel303 (trade name, marketed by Mitsui Cytec Co., Ltd., monomeric melamineresin); 4 parts of 25% dodecylbenzenesulfonic acid solution and 0.5 partof BYK-300 (trade name, marketed by BYK-Chemie Japan K.K., surfacecontrolling agent) was diluted with Swasol #1000 (trade name, marketedby Cosmo Oil Co, Ltd., aromatic hydrocarbon based solvent) to obtain a55% solid content clear coating composition.

[0292] (Note 4) A reactor was charged with 40 parts of Swasol #1000(trade name as above), followed by heating at 120° C., adding a monomermixture of 30 parts of styrene, 35 parts of butyl acrylate, 10 parts of2-ethylhexyl acrylate, 25 parts or hydroxyethyl acrylate and 4 parts ofα,α′-azobisisobutylonitrile over 3 hours and polymerizing to obtain anacrylic resin solution (solid content 70%) having a hydroxy value of 120and a number average molecular weight of 6000.

[0293] (Note 5) A reactor was charged with 58 parts of U-Van 28-60(trade name, marketed by Mitsui Chemicals, Inc., 60% melamine resinsolution), 30 parts of n-heptane and 0.15 part of benzoylperoxide,heating at 95° C., dropping over 3 hours a mixture of 15 parts ofstyrene, 9 parts of acrylonitrile, 13 parts of methyl methacrylate, 15parts of methyl acrylate, 1.8 parts of butyl acrylate, 10 parts ofhydroxyethyl methacrylate, 1.2 parts of acrylic acid, 0.5 part ofbenzoyl peroxide, 5 parts of n-butanol, 30 parts of Shellsol 140 (tradename, marketed by Showa Shell Sekiyu K.K.) and 9 parts of n-heptane,aging for one hour, dropping 0.65 part of t-butylperoctoate and 3.5 partof Shellsol 140 (trade name as above) over one hour, stirring at 95° C.for 2 hours, vacuuming and removing solvent to obtain an acrylic resinnon-water dispersion having a solid content of 60%, and a varnishviscosity A (Gardner bubble viscometer).

[0294] Water Based:

[0295] A mixture of 140 parts of the 50% solid content acrylic resinneutralized solution (Note 1 as above) and 34 parts of Cymel 370 (tradename, marketed by Mitsui Cytec Co., Ltd., 88% water-soluble melamineresin solution) was dispersed, followed by controlling a solid contentof 35% by adding deionized water to obtain a heat-curable water basedclear coating composition.

[0296] Powder Based:

[0297] Everclad 5000 Clear (trade name, marketed by Kansai Paint Co.,Ltd. heat-curable acrylic resin powder coating composition).

[0298] Powder Water Dispersion Based:

[0299] A clear coating composition is prepared by excluding the titaniumwhite in the powder water dispersion coating composition used in theabove heat-curable topcoat colored coating composition.

Example 39

[0300] A 0.8 mm thick aluminum plate material (JIS A6061) was subjectedto a degreasing washing, followed by subjecting to a surface treatmentwith a zinc phosphate based treating agent, coating a cationicelectrodeposition coating composition Elecron GT-10 (blockedpolyisocyanate curing epoxy resin electrodeposition coating composition,trade name, marketed by Kansai Paint Co., Ltd.), heat-curing at 170° C.for 20 minutes so as to obtain an electrodeposition coating plate havinga dry coating film thickness of about 20 μm, spray coating the followingwater based chipping primer coating composition so as to be a dry filmthickness of about 6 μm, heat curing at 100° C. for 20 minutes, spraycoating the following heat-curable water based intercoat coatingcomposition so as to be a film thickness of 30 μm, heat-curing at ₁₄₀°C. for 20 minutes, spray coating a heat-curable topcoat coatingcomposition (Neoamilac #6000 White, trade name, marketed by Kansai PaintCo., Ltd. organic solvent based) so as to be a dry film thickness ofabout 80 μm, and heat-curing at 140° C. for 20 minutes to obtainrespective test coating plate.

Examples 40-64

[0301] Respective test coating plates of Examples 40-64 were prepared inthe manners as described in Tables 4 and 5.

Examples 65-76

[0302] A 0.8 mm thick aluminum plate material (JIS A6061) was subjectedto a degreasing washing, followed by subjecting to a surface treatmentwith a zinc phosphate treating agent to obtain a surface-treatedaluminum material, separately a zinc-iron alloy molten zinc-plated steelplate was subjected to a surface treatment with a zinc phosphatetreating agent, coating a following cationic electrodeposition coatingcomposition so as to be a film thickness of 20 μm, washing with water,heat-curing at 170° C. for 20 minutes to obtain an electrodepositioncoating-treated steel plate, welding the surface-treated aluminummaterial and the coating-treated steel plate so that both coatingsurfaces are in the same side, subjecting both aluminum plate materialand steel plate material to coating under the coating conditions asdescribed in Tables 1 and 2. TABLE 4 (1) Examples Conditions 39 40 41 4243 44 45 46 47 48 49 50 base material aluminum aluminum degree ofsurface 0.2 or less material alloy roughness (μm) surface treatment zincphosphate based treating agent anodized treatment electrodepositioncoating-treated steel plate Electrodeposition coating cationic filmthickness 20 μm ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ electrodeposition predrying 50°C. - 1 minute ◯ ◯ ◯ ◯ heat-curing 170° C. - 20 minute ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯anionic film thickness 20 μm electrodeposition predrying 60° C. - 1minute heat-curing 170° C. - 20 minutes Water based chipping filmthickness 6 μm ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ primer heat-curing 100° C. - 10minutes ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ Intercoat coating water based filmthickness 30 μm ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ intercoat predrying 60° C. - 1minute ◯ ◯ ◯ ◯ coating heat-curing 140° C. - 20 minutes ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯composition powder film thickness 40 μm intercoat predrying 90° C. - 5minutes coating heat-curing 170° C. - 20 minutes composition Topcoatcoating heat-curable kind organic solvent based ◯ ◯ ◯ topcoat coatingwater based ◯ ◯ ◯ composition powder ◯ ◯ ◯ (colored) powder water ◯ ◯ ◯dispersion based film thickness 40 μm ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯heat-curing 140° C. ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ 170° C. 20 minutes ◯ ◯ ◯ ◯ ◯◯ ◯ ◯ ◯ ◯ ◯ ◯ heat-curable base organic solvent based topcoat coatingwater based composition film thickness 20 μm (base/clear) predrying 90°C. - 5 minutes heat-curing 140° C. 170° C. 20 minutes clear organicsolvent based water based powder powder water dispersion based filmthickness 40 μm heat-curing 140° C. 170° C. 20 minutes ultravioletlight- irradiation dose of 150 curable clear mJ/cm² by use of kW topcoatcoating ultrahigh pressure composition mercury lamp Test results coatingfilm smoothness ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ appearance and gloss 93 91 93 9190 92 90 91 92 93 90 91 coating film definition properties 82 81 82 9080 83 87 86 88 83 81 82 performances adhesion properties ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯◯ ◯ ◯ ◯ (aluminum corrosion resistance ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ material)salt water resistance ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ anti-chipping properties ◯◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯

[0303] TABLE 4 (2) Examples Conditions 51 52 53 54 55 56 57 58 59 60 61base material aluminum aluminum degree of surface 0.2 or less materialalloy roughness (μm) surface treatment zinc phosphate based treatingagent anodized treatment electrodeposition coating-treated steel plateElectrodeposition coating cationic film thickness 20 μm ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯◯ ◯ ◯ electrodeposition predrying 60° C. - 1 minute ◯ ◯ heat-curing 170°C. - 20 minutes ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ anionic film thickness 20 μmelectrodeposition predrying 60° C. - 1 minute heat-curing 170° C. - 20minutes Water based chipping film thickness 6 μm ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯primer heat-curing 100° C. - 10 minutes ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ Intercoatcoating water based film thickness 30 μm ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ intercoatpredrying 60° C. - 1 minute ◯ ◯ coating heat-curing 140° C. - 20 minutes◯ ◯ ◯ ◯ ◯ ◯ ◯ composition powder film thickness 40 μm ◯ ◯ intercoatpredrying 90° C. - 5 minutes coating heat-curing 170° C. - 20 minutes ◯◯ composition Topcoat coating heat-curable kind organic solvent based ◯◯ topcoat coating water based composition powder (colored) powder waterdispersion based film thickness 40 μm ◯ ◯ predrying 140° C. ◯ ◯ 170° C.20 minutes ◯ ◯ heat-curable base organic solvent based ◯ topcoat coatingwater based ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ comosition film thickness 20 μm ◯ ◯ ◯ ◯ ◯ ◯◯ ◯ ◯ (base/clear) predrying 90° C. - 5 minutes ◯ ◯ ◯ ◯ ◯ ◯ ◯heat-curing 140° C. ◯ 170° C. ◯ 20 minutes ◯ ◯ ◯ ◯ ◯ clear organicsolvent based ◯ ◯ water based ◯ ◯ ◯ ◯ powder ◯ powder water ◯ dispersionbased film thickness 40 μm ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ heat-curing 140° C. 170° C. ◯◯ ◯ ◯ ◯ ◯ ◯ ◯ 20 minutes ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ultraviolet light- irradiationdose of 150 ◯ curable clear mJ/cm² by use of 3 kW topcoat coatingultrahigh pressure composition mercury lamp Test results coating filmsmoothness ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ appearance and gloss 92 93 93 90 90 9292 93 94 90 89 coating film definition properties 81 82 82 80 80 81 8182 82 80 80 performances adhesion properties ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯(aluminum corrosion resistance ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ material) saltwater resistance ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ anti-chipping properties ◯ ◯ ◯ ◯◯ ◯ ◯ ◯ ◯ ◯ ◯

[0304] TABLE 5 Examples Conditions 62 63 64 65 66 67 68 69 70 71 72 7374 75 76 base material aluminum aluminum degree of surface 0.3 or more0.2 or less material alloy roughness (μm) surface treatment zincphosphate based treating agent anodized treatment ◯ ◯ electrodepositioncoating-treated steel plate ◯ Electrodeposition coating cationic filmthickness 20 μm ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ electrodeposition predrying60° C. - 1 minute ◯ ◯ ◯ ◯ heat-curing 170° C. - 20 minutes ◯ ◯ anionicfilm thickness 20 μm ◯ ◯ electrodeposition predrying 60° C. - 1 minuteheat-curing 170° C. - 20 minutes ◯ ◯ Water based film thickness 6 μm ◯ ◯◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ chipping primer heat-curing 100° C. - 10minutes ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ Intercoat coating water based filmthickness 30 μm ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ intercoat predrying 60° C. - 1minute ◯ ◯ ◯ ◯ ◯ coating heat-curing 140° C. - 20 minutes ◯ ◯ ◯ ◯ ◯ ◯ ◯◯ ◯ ◯ composition powder film thickness 40 μm intercoat predrying 90°C. - 5 minutes coating heat-curing 170° C. - 20 minutes compositionTopcoat coating heat-curable kind organic solvent based ◯ ◯ ◯ ◯ topcoatwater based ◯ ◯ ◯ ◯ coating powder ◯ ◯ ◯ composition powder water(colored) dispersion based film thickness 40 μm ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯◯ ◯ heat-curing 140° C. ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ 170° C. ◯ 20 minutes ◯◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ heat-curable base organic solvent basedtopcoat water based ◯ coating film thickness 20 μm ◯ compositionpredrying 90° C. - 5 minutes ◯ (base/clear) heat-curing 140° C. 170° C.20 minutes clear organic solvent based water based ◯ powder powder waterdispersion based film thickness 40 μm ◯ heat-curing 140° C. 170° C. ◯ 20minutes ◯ ultraviolet light- irradiation dose of 150 curable clearmJ/cm² by use of 3 kW topcoat coating ultrahigh pressure compositionmercury lamp Test results coating film smoothness ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯◯ ◯ ◯ ◯ appearance and gloss 86 85 86 93 91 93 91 90 92 90 91 92 93 9091 coating film definition properties 79 81 83 82 81 82 90 80 83 87 8688 83 81 82 performances adhesion properties ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯◯ (aluminum corrosion resistance ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ material)salt water resistance ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ anti-chippingproperties ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ coating film soothness ◯ ◯ ◯ ◯◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ appearance and gloss 90 88 91 90 88 90 87 85 85 82 83 87coating film definition properties 80 79 80 87 79 81 87 83 84 80 79 80performances adhesion properties ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯(surface-treated corrosion resistance ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ steelplate) salt water resistance ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ anti-chippingproperties ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯

[0305] The electrodeposition coating described in Tables 4 and 5represents the electrodeposition coating method and coating conditionsfor use in the aluminum material.

[0306] In addition to descriptions in Tables 1, 2 and 3, descriptions inTables 4 and 5 include the following description.

[0307] Water based chipping primer coating composition: A resin obtainedby subjecting 10 parts by weight of maleic acid to a graftpolymerization to 100 parts by weight of propylene-ethylene copolymer(weight ratio 70:30, number average molecular weight: about 200000) wasneutralized, followed by obtaining a water dispersion (static glasstransition temperature: −41° C., tensile elongation at break at −20° C.:400%).

Example 77

[0308] A 0.8 mm thick aluminum plate material (JIS A6061) was subjectedto a degreasing washing, followed by subjecting to a surface treatmentwith a zinc phosphate based treating agent, coating a cationicelectrodeposition coating composition Elecron GT-10 (blockedpolyisocyanate curing epoxy resin electrodeposition coating composition,trade name, marketed by Kansai Paint Co., Ltd.), heat-curing at 170° C.for 20 minutes so as to obtain an electrodeposition coating plate havinga dry coating film thickness of about 20 μm spray coating the followingwater based chipping primer coating composition so as to be a dry filmthickness of about 6 W, heat curing at 100° C. for 20 minutes, spraycoating a heat-curable topcoat coating composition (Neoamilac #6000White, trade name, marketed by Kansai Paint Co., Ltd. organic solventbased) so as to be a dry film thickness of about 30 μm, and heat-curingat 140° C. for 20 minutes to obtain respective test coating plate.

Examples 78-98

[0309] Respective test coating plates of Examples 78-98 were prepared inthe same manners as described in Tables 6 and 7.

Examples 99-110

[0310] A 0.8 mm thick aluminum plate material (JIS A6061) was subjectedto a degreasing washing, followed by subjecting to a surface treatmentwith a zinc phosphate treating agent to obtain a surface-treatedaluminum material, separately a zinc-iron alloy molten zinc-plated steelplate was subjected to a surface treatment with a zinc phosphatetreating agent, coating a following cationic electrodeposition coatingcomposition so as to be a film thickness of 20 μm, washing with water,heat-curing at 170° C. for 20 minutes to obtain an electrodepositioncoating-treated steel plate, welding the surface-treated aluminummaterial and the coating-treated steel plate so that both coatingsurfaces are in the same side, subjecting both aluminum plate materialand steel plate material to coating under the coating conditions asdescribed in Tables 1 and 2. TABLE 6 (1) Examples Conditions 77 78 79 8081 82 83 84 85 86 87 88 base material aluminum aluminum degree ofsurface 0.2 or less material alloy roughness (μm) surface treatment zincphosphate based treating agent anodized treatment electrodepositioncoating-treated steel plate Electrodeposition coating cationic filmthickness 20 μm ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ electrodeposition predrying 60°C. - 1 minute ◯ ◯ ◯ ◯ heat-curing 170° C. - 20 minutes ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯anionic film thickness 20 μm electrodeposition predrying 60° C. - 1minute heat-curing 170° C. - 20 minutes Water based chipping filmthickness 6 μm ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ primer heat-cursing 100° - 10minutes ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ Topcoat coating heat-curable kindorganic solvent based ◯ ◯ ◯ topcoat coating water based ◯ ◯ ◯composition powder ◯ ◯ ◯ (colored) powder water ◯ ◯ ◯ dispersion basedfilm thickness 40 μm ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ heat-curing 140° C. ◯ ◯ ◯ ◯◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ 170° C. 20 minutes ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ heat-curablebase organic solvent based topcoat coating water based composition filmthickness 20 μm (base/clear) predrying 90° C. - 5 minutes heat-curing140° C. 170° C. 20 minutes clear organic solvent based water basedpowder powder water dispersion based film thickness 40 μm heat-curing140° C. 170° C. 20 minutes ultraviolet light- irradiation does of 150curable clear mJ/cm² by use of 3 kW topcoat coating ultrahigh pressurecomposition mercury lamp Test results coating film smoothness ◯ ◯ ◯ ◯ ◯◯ ◯ ◯ ◯ ◯ ◯ ◯ appearance and gloss 91 89 91 89 88 90 89 90 90 90 88 87coating film definition properties 72 75 78 77 75 78 75 81 80 78 76 79performances adhesion properties ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ (aluminumcorrosion resistance ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ material) salt waterresistance ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ anti-chipping properties ◯ ◯ ◯ ◯ ◯ ◯◯ ◯ ◯ ◯ ◯ ◯

[0311] TABLE 6 (2) Examples Conditions 89 90 91 92 93 94 95 basematerial aluminum aluminum degree of surface 0.2 or less material alloyroughness (μm) surface treatment zinc phosphate based treating agentanodized treatment electrodeposition coating-treated steel plateElectrodeposition coating cationic film thickness 20 μm ◯ ◯ ◯ ◯ ◯ ◯ ◯electrodeposition predrying 60° C. - 1 minute heat-curing 170° C. - 20minutes ◯ ◯ ◯ ◯ ◯ ◯ ◯ anionic film thickness 20 μm electrodepositionpredrying 60° C. - 1 minute heat-curing 170° C. - 20 minutes Water basedchipping film thickness 6 μm ◯ ◯ ◯ ◯ ◯ ◯ ◯ primer heat-curing 100° C. -1 minute ◯ ◯ ◯ ◯ ◯ ◯ ◯ Topcoat coating heat-curable kind organic solventbased topcoat coating water based composition powder (colored) powderwater dispersion based film thickness 40 μm heat-curing 140° C. 170° C.20 minutes heat-curable base organic solvent based ◯ topcoat coatingwater based ◯ ◯ ◯ ◯ ◯ ◯ composition film thickness 20 μm ◯ ◯ ◯ ◯ ◯ ◯ ◯(base/clear) predrying 90° C. - 5 minutes ◯ ◯ ◯ ◯ ◯ heat-curing 140° C.◯ 170° C. ◯ 20 minutes ◯ ◯ ◯ ◯ ◯ clear organic solvent based ◯ ◯ waterbased ◯ ◯ powder ◯ powder water ◯ dispersion based film thickness 40 μm◯ ◯ ◯ ◯ ◯ ◯ heat-curing 140° C. 170° C. ◯ ◯ ◯ ◯ ◯ ◯ 20 minutes ◯ ◯ ◯ ◯ ◯◯ ultraviolet light- irradiation dose of 150 ◯ curable clear mJ/cm² byuse of 3 kW topcoat coating ultrahigh pressure composition mercury lampTest results coating film smoothness ◯ ◯ ◯ ◯ ◯ ◯ ◯ appearance and gloss89 90 90 89 89 90 91 coating film definition properties 76 75 75 76 7876 78 performances adhesion properties ◯ ◯ ◯ ◯ ◯ ◯ ◯ (aluminum corrosionresistance ◯ ◯ ◯ ◯ ◯ ◯ ◯ material) salt water resistance ◯ ◯ ◯ ◯ ◯ ◯ ◯anti-chipping properties ◯ ◯ ◯ ◯ ◯ ◯ ◯

[0312] TABLE 7 (1) Examples Conditions 96 97 98 99 100 101 102 103 104105 base material aluminum aluminum degree of surface 0.3 or more 0.2 orless material alloy roughness (μ) surface treatment zinc phosphate basedtreating agent anodized treatment ◯ ◯ electrodeposition coating-treatedsteel plate ◯ Electrodeposition coating cationic film thickness 20 μm ◯◯ ◯ ◯ ◯ ◯ ◯ ◯ electrodeposition predrying 60° C. - 1 mintues ◯ ◯heat-curing 170° C. - 20 minutes ◯ ◯ ◯ ◯ ◯ ◯ anionic film thickness 20μm ◯ ◯ electrodeposition predrying 60° C. - 1 minutes heat-curing 170°C. - 20 minutes ◯ ◯ Water based chipping film thickness 6 μm ◯ ◯ ◯ ◯ ◯ ◯◯ ◯ ◯ ◯ primer heat-curing 100° C. - 1 minutes ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯Topcoat coating heat-curable kind organic solvent based ◯ ◯ ◯ ◯ topcoatcoating water based ◯ ◯ ◯ ◯ composition powder ◯ (colored) powder waterdispersion based film thickness 40 μm ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ heat-curing 140°C. ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ 170° C. ◯ 20 minutes ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ heat-curablebase organic solvent based topcoat coating water based ◯ compositionfilm thickness 20 μm ◯ (base/clear) predrying 90° C. - 5 minutes ◯heat-curing 140° C. 170° C. 20 minutes clear organic solvent based waterbased ◯ powder powder water dispersion based film thickness 40 μm ◯heat-curing 140° C. 170° C. ◯ 20 minutes ◯ ultraviolet light-irradiation dose of 150 curable clear mJ/cm² by use of 3 kW topcoatcoating ultrahigh pressure composition mercury lamp Test results coatingfilm smoothness ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ appearance and gloss 84 81 82 91 8991 89 88 90 89 coating film definition properties 75 75 76 72 75 78 7775 78 75 performances adhesion properties ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ (aluminumcorrosion resistance ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ material) salt water resistance◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ anti-chipping properties ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ coatingfilm smoothness ◯ ◯ ◯ ◯ ◯ ◯ ◯ appearance and gloss 86 85 87 86 82 85 80coating film definition properties 75 78 78 81 77 79 75 performancesadhesion properties ◯ ◯ ◯ ◯ ◯ ◯ ◯ (surface-treated corrosion resistance◯ ◯ ◯ ◯ ◯ ◯ ◯ steel plate) salt water resistance ◯ ◯ ◯ ◯ ◯ ◯ ◯anti-chipping properties ◯ ◯ ◯ ◯ ◯ ◯ ◯

[0313] TABLE 7 (2) Examples Conditions 106 107 108 109 110 base materialaluminum aluminum degree of surface 0.2 or less material alloy roughness(μm) surface treatment zinc phosphate based treating agent anodizedtreatment electrodeposition coating-treated steel plateElectrodeposition coating cationic film thickness 20 μm ◯ ◯ ◯ ◯ ◯electrodeposition predrying 60° C. - 1 minutes ◯ ◯ heat-curing 170° C. -20 minutes ◯ ◯ ◯ anionic film thickness 20 μm electrodepositionpredrying 60° C. - 1 minutes heat-curing 170° C. - 20 minutes Waterbased chipping film thickness 6 μm ◯ ◯ ◯ ◯ ◯ primer heat-curing 100°C. - 1 minutes ◯ ◯ ◯ ◯ ◯ Topcoat coating heat-curable kind organicsolvent based topcoat coating water based composition powder ◯ ◯(colored) powder water ◯ ◯ ◯ dispersion based film thickness 40 μm ◯ ◯ ◯◯ ◯ heat-curing 140° C. ◯ ◯ ◯ ◯ ◯ 170° C. 20 minutes heat-curable baseorganic solvent based topcoat coating water based composition filmthickness 20 μm (base/clear) predrying 90° C. - 5 minutes heat-curing140° C. 170° C. 20 minutes clear organic solvent based water basedpowder powder water dispersion based film thickness 40 μm heat-curing140° C. 170° C. 20 minutes ultraviolet light- irradiation dose of 150curable clear mJ/cm² by use of 3 kW topcoat coating ultrahigh pressurecomposition mercury lamp Test results coating film smoothness ◯ ◯ ◯ ◯ ◯appearance and gloss 90 90 90 88 87 coating film definition properties81 80 78 76 79 performances adhesion properties ◯ ◯ ◯ ◯ ◯ (aluminumcorrosion resistance ◯ ◯ ◯ ◯ ◯ material) salt water resistance ◯ ◯ ◯ ◯ ◯anti-chipping properties ◯ ◯ ◯ ◯ ◯ coating film smoothness ◯ ◯ ◯ ◯ ◯appearance and gloss 82 81 79 80 82 coating film definition properties76 78 75 72 72 performances adhesion properties ◯ ◯ ◯ ◯ ◯(surface-treated corrosion resistance ◯ ◯ ◯ ◯ ◯ steel plate) salt waterresistance ◯ ◯ ◯ ◯ ◯ anti-chipping properties ◯ ◯ ◯ ◯ ◯

[0314] The electrodeposition coating described in Tables 6 and 7represents the electrodeposition coating method and coating conditionsfor use in the aluminum material.

[0315] The base material and coating composition in Tables 6 and 7 areas described above, and test methods are as follows.

Example 111

[0316] A 0.8 mm thick aluminum plate material (JIS A6061, Ra 0.2 μm) wassuccessively subjected to degreasing treatment, etching treatment, smatremoval treatment, anodizing treatment on a 170 g/λ sulfuric acidaqueous solution to form a 10 μm thick anodized film, followed bysubjecting to a sealing treatment with deionized water at 80° C. orhigher, coating the following anionic electrodeposition coatingcomposition, and heat curing at 170° C. for 20 minutes to obtain anelectrodeposition coating test plate having a dry coating film thicknessof about 20 μm.

Example 112

[0317] The aluminum material coated with the anodized film as formed inExample 111 was subjected to an alternating current secondaryelectrolysis (15 V, 20° C., 2 to 10 minutes) to obtain a bronzed coloredaluminum material, subjecting to a sealing treatment with a deionizedwater at 80° C. or higher, coating the following anionicelectrodeposition coating composition, heat-curing at 170° C. for 20minutes to obtain an electrodeposition coating test plate having a drycoating film thickness of about 20 μm.

Example 113

[0318] A 0.8 mm thick aluminum plate material (JIS A6061, Ra 0.2 μm) wassuccessively subjected to degreasing treatment, vamite treatment (120 to150° C. steam treatment) to obtain an oxidized film, coating thefollowing anionic electrodeposition coating composition, heat-curing at170° C. for 20 minutes to obtain an electrodeposition coating test platehaving a dry coating film thickness of about 20 μm.

Example 114

[0319] A 0.8 mm thick aluminum plate material (JIS A6061, Ra 0.2 μm) wassuccessively subjected to degreasing treatment, vamite treatment (120 to150° C. steam treatment) to obtain an oxidized film, coating thefollowing cationic electrodeposition coating composition, heat-curing at170° C. for 20 minutes to obtain an electrodeposition coating test platehaving a dry coating film thickness of about 20 μm.

Example 115

[0320] A 0.8 mm thick aluminum plate material (JIS A6061, Ra 0.2 μm) wassubjected to a degreasing treatment, followed by dipping into aphosphate surface treating agent (manganese biphosphate/manganesesilicofluoride/potassium fluoride/zinc acid phosphate/phosphoric acidaqueous solution) at 50° C. for 2 to 5 minutes to form a zincphosphate-treated film, coating the following anionic electrodepositioncoating composition, heat-curing at 170° C. for 20 minutes to obtain anelectrodeposition coating test plate having a dry coating film thicknessof about 20 μm.

Example 116

[0321] A 0.8 mm thick aluminum plate material (JIS A6061, Ra 0.2 μm) wassubjected to a degreasing treatment, followed by dipping into aphosphate surface treating agent (manganese biphosphate/manganesesilicofluoride/potassium fluoride/zinc acid phosphate/phosphoric acidaqueous solution) at 50° C. for 2 to 5 minutes to form a zincphosphate-treated film, coating the following cationic electrodepositioncoating composition, heat-curing at 170° C. for 20 minutes to obtain anelectrodeposition coating test plate having a dry coating film thicknessof about 20 μm.

Example 117

[0322] A 0.8 mm thick aluminum plate material (JIS A6061, Ra 0.2 μm) wassubjected to a degreasing treatment, followed by forming atitanium-treated film by use of the following titanium based surfacetreating agent, coating the following anionic electrodeposition coatingcomposition, heat-curing at 170° C. for 20 minutes to obtain anelectrodeposition coating test plate.

Example 118

[0323] A 0.8 mm thick aluminum plate material (JIS A6061, Ra 0.2 μm) wassubjected to a degreasing treatment, followed by forming atitanium-treated film by use of the following titanium based surfacetreating agent, coating the following cationic electrodeposition coatingcomposition, heat-curing at 170° C. for 20 minutes to obtain anelectrodeposition coating test plate.

Comparative Example 3

[0324] A zinc-iron alloy molten zinc-plated steel plate was subjected toa surface treatment by use of a zinc phosphate treating agent, followedby coating the following anionic electrodeposition coating composition,heat-curing at 170° C. for 20 minutes to obtain an electrodepositioncoating test plate.

Comparative Example 4

[0325] A zinc-iron alloy molten zinc-plated steel plate was subjected toa surface treatment by use of a zinc phosphate treating agent, followedby coating the following cationic electrodeposition coating composition,heat-curing at 170° C. for 20 minutes to obtain an electrodepositioncoating test plate.

[0326] Cationic Electrodeposition Coating Composition:

[0327] Eleclon GT-10 (trade name, marketed by Kansai Paint Co., Ltd.,blocked polyisocyanate-curing epoxy resin electrodeposition coatingcomposition).

[0328] Anionic Electrodeposition Coating Composition:

[0329] Eleclon AG210 (trade name, marketed by Kansai Paint Co., Ltd.,melamine resin-curing acrylic resin electrodeposition coatingcomposition).

[0330] Results are shown in Table 8. TABLE 6 Compara- tive Examples Exs.111 112 113 114 115 116 117 118 3 4 Test Results coating film smoothness◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ Δ appearance and adhesion properties ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ Δ◯ coating film corrosion resistance ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ Δ ◯ performancessalt water resistance ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ Δ ◯ anti-chipping properties ◯ ◯ ◯◯ ◯ ◯ ◯ ◯ Δ ◯

Example 119

[0331] A 08 mm thick aluminum plate material (JIS A6061, Ra 0.2 μm) wassuccessively subjected to degreasing treatment, etching treatment, smatremoval treatment, anodizing treatment in a 170 g/λ sulfuric acidaqueous solution to form a 10 μm thick anodized film (A), followed byspray coating the following heat-curable water based intercoat coatingcomposition so as to be a film thickness of 30 μm, heat-curing at 140°C. for 20 minutes, spray coating a heat-curable topcoat coatingcomposition (Neoamilac #6000 White, trade name, marketed by Kansai PaintCo., Ltd. organic solvent based) so as to be a dry film thickness ofabout 80 μm, and heat-curing at 140° C. for 20 minutes to obtainrespective test coating plate.

Example 120

[0332] The aluminum material coated with the anodized film as formed inExample 111 was subjected to an alternating current secondaryelectrolysis (15 V, 20° C., 2 to 10 minutes) in a 25 g/λ nickel sulfateaqueous solution to obtain a bronzed colored aluminum material (B),subjecting to a sealing treatment with a deionized water at 80° C. orhigher, spray coating the following heat-curable water based intercoatcoating composition so as to be a film thickness of 30 μm, heat-curingat 140° C. for 20 minutes, spray coating a heat-curable topcoat coatingcomposition (Neoamilac #6000 White, trade name, marketed by Kansai PaintCo., Ltd. organic solvent based) so as to be a dry film thickness ofabout 80 μm, and heat-curing at 140° C. for 20 minutes to obtainrespective test coating plate.

Example 121

[0333] A 0.8 mm thick aluminum plate material (JIS A6061, Ra 0.2 μm) wassubjected to degreasing treatment, vamite treatment (120 to 150° C.steam treatment) to obtain an oxidized film (C), followed by spraycoating the following heat-curable water based intercoat coatingcomposition so as to be a film thickness of 30 μm, heat-curing at 140°C. for 20 minutes, spray coating a heat-curable topcoat coatingcomposition (Neoamilac #6000 White, trade name, marketed by Kansai PaintCo, Ltd. organic solvent based) so as to be a dry film thickness ofabout 80 μm, and heat-curing at 140° C. for 20 minutes to obtainrespective test coating plate.

Example 122

[0334] A 0.8 mm thick aluminum plate material (JIS A6061, Ra 0.2 μm) wassubjected to a degreasing treatment, followed by dipping into aphosphate surface treating agent (manganese biphosphate/manganesesilicofluoride/potassium fluoride/zinc acid phosphate/phosphoric acidaqueous solution) at 50° C. for 2 to 5 minutes to form a zincphosphate-treated film (D), spray coating the following heat-curablewater based intercoat coating composition so as to be a film thicknessof 30 μm, heat-curing at 140° C. for 20 minutes, spray coating aheat-curable topcoat coating composition (Neoamilac *6000 White, tradename, marketed by Kansai Paint Co., Ltd. organic solvent based) so as tobe a dry film thickness of about 80 μm, and heat-curing at 140° C. for20 minutes to obtain respective test coating plate.

Example 123

[0335] A 0.8 mm thick aluminum plate material (JIS A6061, Ra 0.2 μm) wassubjected to a degreasing treatment, followed by forming atitanium-treated film (E) by use of the following titanium based surfacetreating agent, spray coating the following heat-curable water basedintercoat coating composition so as to be a film thickness of 30 μm,heat-curing at 140° C. for 20 minutes, spray coating a heat-curabletopcoat coating composition (Neoamilac #6000 White, trade name, marketedby Kansai Paint Co., Ltd. organic solvent based) so as to be a dry filmthickness of about 80 μm, and heat-curing at 140° C. for 20 minutes toobtain respective test coating plate.

[0336] Titanium Based Surface Treating Agent:

[0337] A mixture of 50 parts of 2% titanium based aqueous solution (atitanium-containing yellow translucent viscous 2% solid content titaniumbased aqueous solution prepared by diluting 5 ml of 60% titaniumtetrachloride solution to 500 ml by adding distilled water, followed bydropping ammonia water (1:9) to precipitate titanium hydroxide, washingwith distilled water and adding 10 ml of 30% hydrogen peroxide waterwith agitation; 5 parts of zirconium hydrofluoric acid and 35 parts ofdeionized water.

Examples 124-148

[0338] Respective coating test plates were prepared coating onto theoxidized film-formed aluminum material as in Tables 9 and 10successively the curable water based intercoat coating composition andthe curable topcoat coating composition, followed by heat-curing underthe coating conditions as described in Table 9.

Examples 149-158

[0339] An aluminum material treated by use of the surface treating agentas in Tables 9 and 10 was prepared. Separately the zinc-iron alloymolten zinc-plated steel plate was subjected to a surface treatment byuse of a zinc phosphate treating agent to obtain a surface-treated steelplate, followed by coating the following cationic electrodepositioncoating composition so as to be a film thickness of 20 μm, washing withwater, heat curing at 170° C. for 20 minutes to obtain a coating-treatedsteel plate. The treated aluminum material and the treated steel platewere welded so as to be on the same side, followed by coating both thealuminum material and the steel plate under the coating conditions asdescribed in Table 9. TABLE 9 (1) Examples Conditions 119 120 121 122123 124 125 126 127 128 base material aluminum aluminum degree ofsurface 0.2 or less material alloy roughness (μm) treated film A B C D EA B C D E electrodeposition coating-treated steel plate chipping primerfilm thickness 6 μm coating composition heat-curing 100° C. - 10 minutesIntercoat coating water based film thickness 30 μm ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯intercoat predrying 60° C. - 1 minute ◯ ◯ ◯ ◯ ◯ coating heat-curing 140°C. - 20 minutes ◯ ◯ ◯ ◯ ◯ composition powder film thickness 40 μmintercoat predrying 90° C. - 5 minutes coating heat-curing 170° C. - 20minutes composition Topcoat coating heat-curable kind organic solventbased ◯ ◯ ◯ ◯ ◯ topcoat coating water based ◯ ◯ ◯ ◯ ◯ composition powder(colored) powder water dispersion based film thickness 40 μm ◯ ◯ ◯ ◯ ◯ ◯◯ ◯ ◯ ◯ heat-curing 140° C. 170° C. ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ 20 minutes ◯ ◯ ◯◯ ◯ ◯ ◯ ◯ ◯ ◯ heat-curable base organic solvent based topcoat coatingwater based composition film thickness 20 μm (base/clear) predrying 90°C. - 5 minutes heat-curing 140° C. 170° C. 20 minutes clear organicsolvent based water based powder powder water dispersion based filmthickness 40 μm heat-curing 140° C. 170° C. 20 minutes ultravioletlight- irradiation dose of 150 curable clear mJ/cm² by use of 3 kWtopcoat coating ultrahigh pressure compositions mercury lamp (20 μm)Test results coating film smoothness ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ appearance andgloss 90 89 91 91 90 90 89 91 91 90 coating film definition properties78 77 80 81 80 78 77 80 81 80 performance adhesion properties ◯ ◯ ◯ ◯ ◯◯ ◯ ◯ ◯ ◯ (aluminum corrosion resistance ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ material)salt water resistance ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ anti-chipping properties ◯ ◯ ◯◯ ◯ ◯ ◯ ◯ ◯ ◯

[0340] TABLE 9 (2) Examples Conditions 129 130 131 132 133 134 135 136137 138 base material aluminum aluminum degree of surface 0.2 or lessmaterial alloy roughness (μm) treated film A B C D E D D D A Belectrodeposition coating-treated steel plate Water based chipping filmthickness 6 μm ◯ ◯ ◯ ◯ ◯ primer heat-curing 100° C. - 1 minute ◯ ◯ ◯ ◯ ◯Intercoat coating water based film thickness 30 μm ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯intercoat predrying 60° C. - 1 minute ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ coatingheat-curing 140° C. - 20 minutes powder film thickness 40 μm ◯ intercoatpredrying 90° C. - 5 minutes coating heat-curing 170° C. - 20 minutes ◯composition Topcoat coating heat-curable kind organic solvent basedtopcoat coating water based ◯ ◯ ◯ ◯ ◯ ◯ composition powder ◯ (colored)powder water ◯ dispersion based film thickness 40 μm ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯heat-curing 140° C. 170° C. ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ 20 minutes ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯heat-curable base organic solvent based topcoat coating water based ◯ ◯composition film thickness 80μm ◯ ◯ (base/clear) predrying 90° C. - 5minutes ◯ ◯ heat-curing 140° C. 170° C. 20 minutes ◯ ◯ clear organicsolvent based water based ◯ ◯ powder powder water dispersion based filmthickness 40μm ◯ ◯ heat-curing 140° C. ◯ ◯ 170  C. 20 minutes ◯ ◯ultraviolet light- irradiation dose of 150 curable clear mJ/cm² by useof 3 kW topcoat coating ultrahigh pressure compostion mercury lamp(20μm) Test results coating film smoothness ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯appearance and gloss 91 90 92 92 91 92 90 90 92 91 coating filmdefinition properties 79 78 81 82 81 82 80 80 80 79 performancesadhesion properties ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ (aluminum corrosion resistance ◯◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ material) salt water resistance ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯anti-chipping properties ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯

[0341] TABLE 9 (3) Examples Conditions 139 140 141 142 143 144 145 basematerial aluminum aluminum degree of surface 0.2 or less material alloyroughness (μm) treated film C D E D D D D electrodepositioncoating-treated steel plate Water based chipping film thickness 6 μmprimer heat-curing 100° C. - 1 minute Intercoat coating water based filmthickness 30 μm ◯ ◯ ◯ ◯ ◯ ◯ ◯ intercoat predrying 60° C. - 1 minute ◯ ◯◯ coating heat-curing 140° C. - 20 minutes ◯ ◯ ◯ ◯ composition powderfilm thickness 40 μm intercoat predrying 90° C. - 5 minutes coatingheat-curing 170° C. - 20 minutes composition Topcoat coatingheat-curable kind organic solvent based topcoat coating water basedcomposition powder (colored) powder water dispersion based filmthickness 40 μm heat-curing 140° C. 170° C. 20 minutes heat-curable baseorganic solvent based ◯ topcoat coating water based ◯ ◯ ◯ ◯ ◯ ◯composition film thickness 20 μm ◯ ◯ ◯ ◯ ◯ ◯ ◯ (base/clear) predrying90° C. - 5 minutes ◯ ◯ ◯ heat-curing 140° C. ◯ ◯ ◯ 170° C. ◯ 20 minutes◯ ◯ ◯ ◯ ◯ ◯ ◯ clear organic solvent based water based ◯ ◯ ◯ ◯ powder ◯powder water ◯ dispersion based film thickness 40 μm ◯ ◯ ◯ ◯ ◯ ◯heat-curing 140° C. ◯ ◯ ◯ ◯ 170° C. ◯ ◯ 20 minutes ◯ ◯ ◯ ◯ ◯ ◯ultraviolet light- irradiation dose of 150 ◯ curable clear mJ/cm² by useof 3 kW topcoat coating ultrahigh pressure composition mercury lamp (20μm) Test results coating film smoothness ◯ ◯ ◯ ◯ ◯ ◯ ◯ appearance andgloss 93 94 92 90 90 92 coating film definition properties 82 82 81 8278 78 82 performance adhesion properties ◯ ◯ ◯ ◯ ◯ ◯ ◯ (aluminumcorrosion resistance ◯ ◯ ◯ ◯ ◯ ◯ ◯ material) salt water resistance ◯ ◯ ◯◯ ◯ ◯ ◯ anti-chipping properties ◯ ◯ ◯ ◯ ◯ ◯ ◯

[0342] TABLE 10 Examples Conditions 146 147 148 149 150 151 152 153 154155 156 157 158 base material aluminum aluminum degree of surface 0.3 ormore 0.2 or less material alloy roughness (μm) treated film D D D A B CD E A B C D E electrodeposition coating-treated steel plate ◯ Chippingfilm thickness 6 μm primer heat-curing 100° C. - 10 minutes coatingcomposition Intercoat coating water based film thickness 30 μm ◯ ◯ ◯ ◯ ◯◯ ◯ ◯ ◯ ◯ ◯ intercoat predrying 60° C. - 1 minute ◯ ◯ ◯ ◯ ◯ ◯ coatingheat-curing 140° C. - 20 minutes ◯ ◯ ◯ ◯ ◯ ◯ ◯ composition powder filmthickness 40 μm intercoat predrying 90° C. - 5 minutes coatingheat-curing 170° C. - 20 minutes composition Topcoat coatingheat-curable kind organic solvent ◯ topcoat based coating water based ◯◯ ◯ ◯ ◯ ◯ composition powder ◯ ◯ ◯ ◯ ◯ (colored) powder water dispersionbased film thickness 40 μm ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ heat-curing 140° C.170° C. ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ 20 minutes ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯heat-curable base organic solvent topcoat based coating water based ◯composition film thickness 20 μm ◯ (base/clear) predrying 90° C. - 5minutes ◯ heat-curing 140° C. 170° C. 20 minutes clear organic solventbased water based ◯ powder powder water dispersion based film thickness40 μm ◯ heat-curing 140° C. 170° C. ◯ 20 minutes ◯ ultravioletirradiation dose of 150 light-curable mJ/cm² by use of 3 kW cleartopcoat ultrahigh pressure coating mercury lamp (20 μm) composition Testresults coating film smoothness ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ appearancegloss 88 88 90 90 89 91 91 90 90 89 92 92 90 and definition properties76 77 88 78 77 80 81 80 80 79 80 81 80 coating film adhesion properties◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ performance corrosion resistance ◯ ◯ ◯ ◯ ◯ ◯ ◯◯ ◯ ◯ ◯ ◯ ◯ (aluminum salt water resistance ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯material) anti-chipping properties ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ coatingfilm smoothness ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ appearance gloss 88 89 89 89 89 8988 87 90 90 88 and coating definition properties 86 77 77 77 77 77 78 7778 80 78 film adhesion properties ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ performancecorrosion resistance ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ (surface- salt waterresistance ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ treated steel anti-chipping properties◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ plate)

Comparative Examples 5-6

[0343] Respective coating test plates of Comparative Examples 5-6 wereprepared in the same manner as in Table 11. TABLE 11 Comparative Exa.Conditions 5 6 base material aluminum material aluminum alloy degree ofsurface 0.5 or roughness more (μm) treated film electrodepositioncoating-treated steel plate ◯ Chipping primer coating film thickness 6μm composition heat-curing 100° C. - 10 minutes Intercoat coating waterbased film thickness 30 μm intercoat coating predrying 60° C. - 1 minutecomposition heat-curing 140° C. - 20 minutes powder intercoat filmthickness 40 μm coating composition predrying 90° C. - 5 minutesheat-curing 170° C. - 20 minutes Topcoat coating heat-curable kindorganic solvent based ◯ ◯ topcoat coating water based composition powder(colored) powder water dispersion based film thickness 40 μm ◯ ◯heat-curing 140° C. ◯ ◯ 170° C. 20 minutes ◯ ◯ Test results coating filmsmoothness Δ Δ appearance and gloss 70 65 coating film definitionproperties 65 60 performances adhesion properties ◯ ◯ (aluminummaterial) corrosion resistance ◯ ◯ salt water resistance ◯ ◯anti-chipping properties Δ Δ

[0344] The electrodeposition coating described in Tables 9, 10 and 11represents the electrodeposition coating method and coating conditionsfor use in the aluminum material.

[0345] The base material and coating composition in Tables 9, 10 and 11are as described above, and test methods are as follows.

Example 159

[0346] A 0.8 mm thick aluminum plate material having a bent part (JISA6061, Ra0.2 μm) was successively subjected to degreasing treatment,etching treatment, smat removal treatment, anodizing treatment in a 170g/l sulfuric acid aqueous solution to form a 10 μm thick anodized film(A), followed by applying the following film facing material (1) ontothe surface of the cementing material with the results that the filmfacing material showed good appearance without coating film drawbackssuch as wrinkles, blisters, bubbling, reduction in gloss, separation,cracks and the like in both bent area and plane area.

[0347] The film facing material was dipped into a tap water at 40° C.for 20 days, followed by examining coating film drawbacks such asseparation, blisters, reduction in gloss and the like with the resultthat nothing was abnormal to be good.

[0348] The anti-chipping properties test was carried and as follows.No.7 ground stone (100 g) was sprayed onto the surface of the coatingfilm at an angle of 90° to the surface of the coating film, followed bysubjecting the stone-sprayed surface to a separation test by use of agum tape to evaluate as follows. ∘: no separation of coating film wasobserved; Δ: slight separation of coating film was observed; X:remarkable separation of coating film was observed. The test result wasevaluated as ∘ to be good.

Example 160

[0349] The aluminum material coated with the anodized film as formed inExample 159 was subjected to an alternating current secondaryelectrolysis (15 V, 20° C., 2 to 10 minutes) in a 25 g/l nickel sulfateaqueous solution to obtain a bronzed colored aluminum material (B),followed by applying the following film facing material (1) onto thesurface of the cementing material with the result that the film facingmaterial showed good appearance without coating film drawbacks such aswrinkles, blisters, bubbling, reduction in gloss, separation, cracks andthe like.

[0350] The film facing material was dipped into a tap water at 40° C.for 20 days, followed by examining coating film drawbacks such asseparation, blisters, reduction in gloss and the like with the resultthat nothing was abnormal to be good.

[0351] The anti-chipping properties test result was evaluated as ∘ to begood.

Example 161

[0352] A 0.8 mm thick aluminum plate material (JIS A6061, Ra 0.2 μm) wassubjected to degreasing treatment, vamite treatment (120 to 150° C.steam treatment) to obtain an oxidized film(C), followed by applying thefollowing film facing material(1) onto the surface of the cementingmaterial, with the result that the film facing material showed goodappearance without coating film drawbacks such as wrinkles, blisters,bubbling, reduction in gloss, separation, cracks and the like.

[0353] The film facing material was dipped into a tap water at 40° C.for 20 days, followed by examining coating film drawbacks such asseparation, blisters, reduction in gloss and the like with the resultthat nothing was abnormal to be good.

[0354] The anti-chipping properties test result was evaluated as ∘ to begood.

Example 162

[0355] A 0.8 mm thick aluminum plate material having a bent part (JIS A6061, Ra 0.2 μm) was subjected to a degreasing treatment, followed bydipping into a phosphate surface heating agent (manganesebiphosphate/manganese silicofluoride/potassium fluoride/zinc acidphosphate/phophoric acid aqueous solution) at 50° C. for 2 to 5 minutesto form a zinc phosphate-treated film (D), followed by applying thefollowing film facing material (1) onto the surface of the cementingmaterial with the result that the film facing material showed goodappearance without coating film drawbacks such as wrinkles, blisters,bubbling, reduction in gloss, separation, cracks and the like.

[0356] The film facing material was dipped into a tap water at 40° C.for 20 days, followed by examining coating film drawbacks such asseparation, blisters, reduction in gloss and the like with the resultthat nothing was abnormal to be good.

[0357] The anti-chipping properties test result was evaluated as ∘ to begood.

Example 163

[0358] A 0.8 mm thick aluminum plate material (JIS A6061, Ra 0.2 μm) wassubjected to decreasing treatments followed by forming atitanium-treated film(E) by use of the following titanium based surfacetreating agent, followed by applying the following film facing material(1) onto the surface of the cementing material with the result that thefilm facing material showed good appearance without coating filmdrawbacks such as wrinkles, blisters, bubbling, reduction in gloss,reparation, cracks and the like.

[0359] The film facing material was dipped into a tap water at 40° C.for 20 days, followed by examining coating film drawbacks such asseparation, blisters, seduction in gloss and the like with the resultthat nothing was abnormal to be good.

[0360] The anti-chipping properties test result was evaluated as ∘ to begood.

[0361] Titanium based surface treating agent: A mixture of 50 parts of2% titanium based aqueous solution (a titanium-containing yellowtranslucent viscous 2% solid content titanium based aqueous solutionprepared by diluting 5 ml of 60% titanium tetrachloride solution to 500ml by adding distilled water, followed by dropping ammonia water (1:9)to precipitate titanium hydroxide, washing with distilled water andadding 10 ml of 30% hydrogen peroxide water with agitation; 5 parts ofzirconium hydrofluoric acid and 35 parts of deionized water.

Example 164

[0362] An aluminum material subjected to the vamite treatment (120-150°C. steam treatment) to form the oxidized film(C) was subjected to thecationic electrodeposition coating by use of Eleclon GT-10(trade name,marketed by Kansai Paint Co., Ltd., blocked polyisocyanate curing epoxyresin electrodeposition coating composition, gray), followed byheat-curing at 170° C. for 20 minutes to form an electrodepositioncoating test plate, followed by applying the following film facingmaterial (1) onto the surface of the cementing material with the resultthat the film facing material showed good appearance without coatingfilm, drawbacks such as wrinkles, blisters, bubbling, reduction ingloss, separation, cracks and the like.

[0363] The film facing material was dipped into a tap water at 40° C.for 20 days, followed by examining coating film drawbacks such asseparation, blisters, seduction in gloss and the like with the resultthat nothing was abnormal to be good.

[0364] The anti-chipping properties test result was evaluated as ∘ to begood.

Example 165

[0365] An aluminum material subjected to the vamite treatment (120-150°C. steam treatment) to form the oxidized film(C) was subjected to thecationic electrodeposition coating by use of Eleclon GT-10(trade name,marketed by Kansai Paint Co., Ltd., blocked polyisocyanate curing epoxyresin electrodeposition coating composition, gray), followed byheat-curing at 170° C. for 20 minutes to form an electrodepositioncoating test plate, followed by spray coating the following water basedchipping primer coating composition to be a dry coating film thicknessof about 6 μm, heat-curing at 100° C. for 20 minutes, followed byapplying the following film facing material (1) onto the surface of thecementing material with the result that the film facing material showedgood appearance without coating film drawbacks such as wrinkles,blisters, bubbling, reduction in gloss, separation, cracks and the like.

[0366] The film facing material was dipped into a tap water at 40° C.for 20 days, followed by examining coating film drawbacks such asseparation, blisters, seduction in gloss and the like with the resultthat nothing was abnormal to be good.

[0367] The anti-chipping properties test result was evaluated as ∘ to begood.

Example 166

[0368] An aluminum material subjected to the vamite treatment (120-150°C. steam treatment) to form the oxidized film(C) was subjected to thecationic electrodeposition coating by use of Eleclon GT-10(trade name,marketed by Kansai Paint Co., Ltd., blocked polyisocyanate curing epoxyresin electrodeposition coating composition, gray), followed byheat-curing at 170° C. for 20 minutes to form an electrodepositioncoating test plate, followed by spray coating the following water basedchipping primer coating composition to be a dry coating film thicknessof about 6 μm, heat-curing at 100° C. for 0.20 minutes, followed byspray coating the following heat-curable water based intercoat coatingcomposition so as to be a film thickness of 30 μm, heat-curing at 140°C. for 20 minutes, followed by applying the following film facingmaterial (1) onto the surface of the cementing material with the resultthat the film facing material showed good appearance without coatingfilm drawbacks such as wrinkles, blisters, bubbling, reduction in gloss,separation, cracks and the like.

[0369] The film facing material was dipped into a tap water at 40° C.,for 20 days, followed by examining coating film drawbacks such asseparation, blisters, seduction in gloss and the like with the resultthat nothing was abnormal to be good.

[0370] The anti-chipping properties test result was evaluated as ∘ to begood.

Example 167

[0371] The following film facing material (2) was applied onto thesurface of the bronzed colored aluminum material (B) through the surfaceof the cementing material, with the result that the film facing materialshowed good appearance without coating film drawbacks such as wrinkles,blisters, bubbling, reduction in gloss, separation, cracks and the like.

[0372] The resulting film facing material showed excellent properties infinish appearance with high chroma, which properties were impossible inthe case where the conventional coating film is formed directly onto theautomobile body.

[0373] The film facing material was dipped into a tap water at 40° C.for 20 days, followed by examining coating film drawbacks such asseparation, blisters, seduction in gloss and the like with the resultthat nothing was abnormal to be good.

[0374] The anti-chipping properties test result was evaluated as ∘ to begood.

Example 168

[0375] An anionic electrodeposition coating composition (Eleclon AG,trade name, marketed by Kansai Paint Co., Ltd., melamine resin-curingacrylic resin electrodeposition coating composition, clear) was coatedonto the bronzed colored aluminum material (B), followed by heat-curingat 170° C. for 20 minutes to obtain an electrodeposition coating testplate having a dry coating film thickness of about 20 μm, followed byapplying the following film facing material (3) onto the surface of thebronzed colored aluminum material (B) through the surface of thecementing material, with the result that the film facing material showedgood appearance without coating film drawbacks such as wrinkles,blisters, bubbling, reduction in gloss, separation, cracks and the like.

[0376] The resulting film facing material showed excellent properties infinish appearance with high chroma, which properties were impossible inthe case where the conventional coating film is formed directly onto theautomobile body.

[0377] The film facing material was dipped into a tap water at 40° C.for 20 days, followed by examining coating film drawbacks such asseparation, blisters, reduction in gloss and the like with the resultthat nothing was abnormal to be good.

[0378] The anti-chipping properties test result was evaluated as ∘ to begood.

Example 169

[0379] An anionic electrodeposition coating composition (Eleclon AG,trade name, marketed by Kansai Paint Co., Ltd., melamine resin-curingacrylic resin electrodeposition coating composition, clear) was coatedonto the bronzed colored aluminum material (B), followed by heat-curingat 170° C. for 20 minutes to obtain an electrodeposition coating testplate having a dry coating film thickness of about 20 μm, followed byapplying the following film facing material (3) onto the surface of thebronzed colored aluminum material (B) through the surface of thecementing material, with the result that the film facing material showedgood appearance without coating film drawbacks such as wrinkles,blisters, bubbling, reduction in gloss separation, cracks and the like.

[0380] The resulting film facing material showed excellent properties infinish appearance with high chroma, which properties were impossible inthe case where the conventional coating film is formed directly onto theautomobile body.

[0381] The film facing material was dipped into a tap water at 40° C.for 20 days, followed by examining coating film drawbacks such asseparation, blisters, reduction in gloss and the like with the resultthat nothing was abnormal to be good.

[0382] The anti-chipping properties test result was evaluated as ∘ to begood.

Example 170

[0383] A automobile body outer plate excluding a bonnet part (zinc-ironalloy molten zinc-plated steel plate) was subjected to a surfacetreatment by use of a zinc phosphate treating agent, followed by coatinga cationic electrodeposition coating composition so as to be a dry filmthickness of 20 μm, washing with water, heat-curing at 170° C. for 20minutes to obtain an electrodeposition coat-treated steel plate, spraycoating the following heat-curable water based intercoat coatingcomposition so as to be a dry film thickness of 30 μm, heat-curing at140° C. for 20 minutes, spray coating the following clear composition{circle over (1)} so as to be a dry film thickness of 20 μm, heat-curingat 100° C. for 10 minutes, spray coating the following clear composition{circle over (1)} so as to be a dry film thickness of 20 μm, heat-curingat 140° C. for 20 minutes.

[0384] Separately, the following film facing material (1) was appliedonto an aluminum material with the zinc phosphate-treated film (D)through the surface of the cementing material. Both steel plate andaluminum material was assembled to form an automobile body, with theresult that the film facing material showed good appearance withoutcoating film drawbacks such as wrinkles, blisters, bubbling, reductionin gloss, separation, cracks and the like.

[0385] The film facing material was dipped into a tap water at 40° C.for 20 days, followed by examining coating film drawbacks such asseparation, blisters, reduction in gloss and the like with the resultthat nothing was abnormal to be good.

[0386] The anti-chipping properties test result was evaluated as ∘ to begood

Comparative Example 7

[0387] A zinc-iron alloy molten zinc-plated steel plate was subjected toa surface treatment by use of a zinc phosphate treating agent, followedby spray coating the following heat-curable water based intercoatcoating composition so as to be a dry film thickness of 30 μm,heat-curing at 140° C. for 20 minutes, spray coating the following pearlgloss composition {circle over (1)} so as to be a dry film thickness of20 μm, heat-curing at 100° C. for 10 minutes, spray coating thefollowing clear composition {circle over (1)} so as to be a dry filmthickness of 20 μm, and heat-curing at 140° C. for 20 minutes, with theresult that the resulting coating film showed reduction in gloss, orangepeel, pinholes compared with Examples.

[0388] The anti-chipping properties was evaluated as A. Water basedchipping primer coating composition: A resin obtained by subjecting 10parts by weight of maleic acid to a graft polymerization to 100 parts byweight of propylene-ethylene copolymer (weight ratio 70:30, numberaverage molecular weight: about 200000) was neutralized, followed byobtaining a water dispersion(static glass transition tenperation:−41°C., tensile elongation at break at −20° C.(:400%)

[0389] Intercret Wating Composition:

[0390] (Lugabake intercoat coating composition, gray, trade name,marketed by Kansai Paint Co., Ltd., polyester resin melamine resinbased, organic solvent based) was subjected to an electrostatic spraycoating so as to be a dry film thickness of 40 μm, followed byheat-curing at 140° C. for 30 minutes.

[0391] Film Facing Material (1) (Colored):

[0392] The following pearl gloss composition {circle over (1)} wasscreen printed onto a polyethylene terephthalate film (50 μm) so as tobe a dry film thickness of 20 μm, heat-curing at 100° C. for 10 minutes,screen printing the following clear composition {circle over (1)} so asto be a dry film thickness of 20 μm, heat-curing at 100° C. for 10minutes, and laminating an acrylic resin based pressure-sensitiveadhesive (30 μm).

[0393] The Pearl Gloss Composition {circle over (1)}:

[0394] An organic solvent based ink comprising 70 parts of hydroxylgroup-containing acrylic resin (hydroxy value 100, number averagemolecular weight 20000), 30 parts of hexamethylene diisocyanatecrosslinking agent, and 10 parts of titanium oxide-coated flake mica(diameter maximum) 10 to 20 μm, thickness 0.5 to 1 μm, optical thicknessof titanium oxide about 140 nm, geometrical thickness about 60 μm, tradename, Ilyozine 03R, marketed by Merk Co., Ltd.).

[0395] Clear Composition {circle over (1)};

[0396] An organic solvent based ink comprising 70 parts of hydroxylgroup-containing acrylic resin (hydroxy value 100, number averagemolecular weight 20000) and 30 parts of hexamedylene diisocyanatecrosslinking agent.

[0397] Film Facing Material (2) Clear:

[0398] The clear composition {circle over (1)} was screen printed ontothe surface of polyethylene terephthalate film (50 μm) so as to be a dryfilm thickness of 20 μm, followed by heat-curing at 100° C. for 10minutes, and laminating an acrylic resin based presure-sensitiveadhesive (30 μm) onto the back side of the polyethylene terephthalutefilm.

[0399] Film Facing Material (3)(Pattern Printed):

[0400] A pearl gloss composition {circle over (1)} was scream printedonto the one side of a releasable polyethylene terephthalate film layer(application film) by use of a knife coater so as to be a dry filmthickness of 30 μm and to obtain a marble pattern, and heat-curing at80° C. for 15 minutes to obtain a laminate film.

[0401] Separately, an acrylic resin based presure-sensitive adhesive (16μm)was onto the release-treated film surface to obtain an adhesive film.

[0402] The pearl gloss surface of the laminate film was faced to thesurface of the acrylic resin based pressure-sensitive adhesive layer,followed by pressing and cementing to obtain a transfer film laminatingapplication film/Retan PG-80 (clear)/acrylic resin basedpressure-sensitive adhesive/release-treated film.

What is claimed is:
 1. An automobile body-coating method which comprisesoptionally subjecting an outer plate area and/or an inner plate area ofan automobile body comprising an aluminum material, an aluminummaterial-coated steel material or an aluminum material and steelmaterial-combined metal material to a surface treatment, successivelyfollowed by coating a heat-curable electrodeposition coating compositionto form a curable electrodeposition coating film, (1) coating aheat-curable water based intercoat coating composition to form a waterbased intercoat coating film or coating a heat-curable intercoat powdercoating composition to form an intercoat powder coating film, (2)coating a water based chipping primer to form a water based chippingprimer coating film followed by coating a heat-curable water basedintercoat coating composition to form a water based intercoat coatingfilm or coating a heat-curable intercoat powder coating composition toform an intercoat powder coating film, or (3) coating a water basedchipping primer to form a water based chipping primer coating film, andcoating a topcoat coating composition to form a curable topcoat coatingfilm, respective coating films being heat-cured independently from eachother to cure all of the respective coating films, or at least onemulti-layer coating film selected from the group consisting ofsuccessively formed at least two-layer coating films being heat-curedsimultaneously and at least one remaining coating film beingindependently cured respectively.
 2. An automobile body-coating methodfor coating an outer plate area and/or an inner plate area of anautomobile body comprising an oxidized aluminum material or an oxidizedaluminum material and steel material-combined metal material, whichmethod comprises (1) electrodeposition coating a heat-curableelectrodeposition coating composition onto the surface of the oxidizedaluminum material in the outer plate area and/or the inner plate area ofthe automobile body to form an electrodeposition coating film followedby heat curing, optionally the steel material being subjected to asurface treatment followed by being subjected to an electrodepositioncoating, or (2) coating a heat-curable water based intercoat coatingcomposition or a heat-curable intercoat powder coating composition ontothe outer plate area and/or the inner plate area of the automobile bodyto form a water based intercoat coating film or an intercoat powdercoating film respectively, followed by coating a curable topcoat coatingcomposition to form a curable topcoat coating film, and heat curing bothcoating films independently from each other or simultaneously,optionally the steel material being subjected to an electrodepositioncoating.
 3. An automobile body-coating method which comprises applying afilm facing material onto the surface of an aluminum material or analuminum material-coated steel